Organic Chemistry Naming Examples  4

WEBVTT
Kind: captions
Language: en

00:00:00.450 --> 00:00:03.550
Let's see if we can name
this guy right here.

00:00:03.550 --> 00:00:06.790
In all of these problems, I
guess you can call them, we

00:00:06.790 --> 00:00:09.456
look for the longest chain or
the longest ring, and this one

00:00:09.456 --> 00:00:10.490
is pretty obvious here.

00:00:10.490 --> 00:00:14.130
The ring in the middle is
clearly the longest carbon

00:00:14.130 --> 00:00:14.830
structure here.

00:00:14.830 --> 00:00:19.470
It has one, two, three,
four, five, six,

00:00:19.470 --> 00:00:21.800
seven, eight carbons.

00:00:21.800 --> 00:00:23.020
Let me highlight that.

00:00:23.020 --> 00:00:28.570
It is eight carbons, so we will
be you using the prefix

00:00:28.570 --> 00:00:33.830
oct-, and it is in a cycle, so
it will be cyclooct-, and it's

00:00:33.830 --> 00:00:36.500
all single bonds, so
it's cyclooctane.

00:00:36.500 --> 00:00:40.106
This right here tells us that
our core is cyclooctane.

00:00:43.970 --> 00:00:45.890
Now let's look at the different
subgroups or the

00:00:45.890 --> 00:00:49.660
different branches off
of the main ring.

00:00:49.660 --> 00:00:54.760
Over here, we have a one, two,
three, four-carbon group.

00:00:54.760 --> 00:01:01.040
It is in a cycle or it's in
a ring, so this is cyclo-.

00:01:01.040 --> 00:01:06.420
Four carbons are but-,
cyclobutyl, -yl because it's a

00:01:06.420 --> 00:01:10.710
subgroup or it's off of the main
chain or the main ring,

00:01:10.710 --> 00:01:14.390
so that is our cyclobutyl
right there.

00:01:14.390 --> 00:01:17.000
We also have another cyclobutyl
right here, four

00:01:17.000 --> 00:01:20.330
carbons in a ring, so that's
another cyclobutyl.

00:01:24.670 --> 00:01:28.400
Up here, we have three
carbons in a cycle.

00:01:28.400 --> 00:01:31.920
The prefix for three carbons
is prop-, so this is

00:01:31.920 --> 00:01:33.170
cyclopropyl.

00:01:40.330 --> 00:01:43.070
Then down here, let's start with
the common names, because

00:01:43.070 --> 00:01:45.020
those tend to be a little
bit easier.

00:01:45.020 --> 00:01:49.850
We have one, two, three,
four carbons.

00:01:49.850 --> 00:01:51.520
Actually, we have it
there and there.

00:01:51.520 --> 00:01:56.330
One, two, three, four, these
are the same groups.

00:01:56.330 --> 00:01:58.800
We're going to be dealing with
but- if we do common names,

00:01:58.800 --> 00:02:00.110
and you see it has
this Y shape.

00:02:00.110 --> 00:02:03.255
We're kind of connected to the
base of the Y in either case,

00:02:03.255 --> 00:02:05.790
so we are dealing
with isobutyl.

00:02:11.890 --> 00:02:14.070
The Y shape tells us that we're

00:02:14.070 --> 00:02:16.500
dealing with iso-, isobutyl.

00:02:16.500 --> 00:02:18.530
That's both of these
right there.

00:02:18.530 --> 00:02:21.020
Now, we have to figure out how
we're going to number, where

00:02:21.020 --> 00:02:23.520
we're going to number ourselves
on this ring.

00:02:23.520 --> 00:02:30.770
And to do that, we look for
the group that is first

00:02:30.770 --> 00:02:32.590
alphabetically.

00:02:32.590 --> 00:02:35.200
This is a little bit of a
confusing point sometimes.

00:02:35.200 --> 00:02:37.940
If this was a tert-butyl or
sec-butyl, we would consider

00:02:37.940 --> 00:02:40.900
the B, but when it's isobutyl,
it's all considered one word,

00:02:40.900 --> 00:02:42.370
so we'll consider the I.

00:02:42.370 --> 00:02:49.950
We need to compare the I to the
C, to the C, to the C, so

00:02:49.950 --> 00:02:52.170
the C's definitely
win out on the I.

00:02:52.170 --> 00:02:55.580
If we look at all of these
cyclos, cyclobutyl definitely

00:02:55.580 --> 00:02:57.350
takes precedence over
cyclopropyl.

00:02:57.350 --> 00:02:59.960
It comes first alphabetically.

00:02:59.960 --> 00:03:03.350
Let's make our starting point
this cyclobutyl, although you

00:03:03.350 --> 00:03:06.150
could have made it that
cyclobutyl as well, so we'll

00:03:06.150 --> 00:03:07.880
make that our starting point.

00:03:07.880 --> 00:03:10.220
We're going to go in a clockwise
direction, so that

00:03:10.220 --> 00:03:12.690
we could get to this one first,
so that the next group

00:03:12.690 --> 00:03:13.580
is only going to be a two.

00:03:13.580 --> 00:03:15.260
Otherwise, the next group would
have been at three.

00:03:15.260 --> 00:03:24.050
So one, two, three, four, five,
six, seven, so this is a

00:03:24.050 --> 00:03:25.960
1-cyclobutyl.

00:03:25.960 --> 00:03:28.230
This is a 6-cyclobutyl.

00:03:28.230 --> 00:03:29.590
This is a 7-cyclopropyl.

00:03:32.200 --> 00:03:36.580
This is a 2-isobutyl, so this is
a 2-isobutyl and this is a

00:03:36.580 --> 00:03:37.850
4-isobutyl.

00:03:37.850 --> 00:03:40.090
We want to write them all
in alphabetical order.

00:03:40.090 --> 00:03:46.160
The cyclobutyls win, so we
have a cyclobutyl at one.

00:03:46.160 --> 00:03:48.130
We have a 1-cyclobutyl.

00:03:48.130 --> 00:03:50.320
We also have a 6-cyclobutyl.

00:03:50.320 --> 00:03:51.900
we have two of them, so
it is dicyclobutyl.

00:03:55.570 --> 00:03:57.820
Let me capitalize since that's
where we're starting.

00:04:03.570 --> 00:04:06.580
So we got those two guys out
of the way, and then

00:04:06.580 --> 00:04:10.620
alphabetically, cyclopropyl
is next, so then we have a

00:04:10.620 --> 00:04:12.980
7-cyclopropyl.

00:04:12.980 --> 00:04:15.120
Let me do that in that orange
color of the cyclopropyl.

00:04:18.079 --> 00:04:25.660
7-cyclopropyl, got that
guy out of the way.

00:04:25.660 --> 00:04:30.610
Then at two and four we
have an isobutyl.

00:04:30.610 --> 00:04:35.570
We have a 2,4-, and we have
two of them, so it is

00:04:35.570 --> 00:04:49.160
diisobutyl, and then finally
cyclooctane.

00:04:49.160 --> 00:04:54.320
We got the 2,4-diisobutyls out
of the way, and then we have

00:04:54.320 --> 00:04:56.540
our cyclooctane, so I'll just
write the cyclooctane.

00:05:01.750 --> 00:05:02.810
And we're done.

00:05:02.810 --> 00:05:04.420
This was the common naming.

00:05:04.420 --> 00:05:06.370
Now, if we want to do systematic
naming, we would

00:05:06.370 --> 00:05:09.460
have to use something else
other than the isobutyl.

00:05:09.460 --> 00:05:13.010
And to do that, let me
do that over here.

00:05:13.010 --> 00:05:17.300
What you do is you use your
connection point as one, and

00:05:17.300 --> 00:05:18.520
you just branch.

00:05:18.520 --> 00:05:20.240
Let me do this in a color I
haven't used for before.

00:05:20.240 --> 00:05:20.510
Green.

00:05:20.510 --> 00:05:24.370
So let's make that our core
chain, so that is one, two,

00:05:24.370 --> 00:05:28.990
three, carbons, so it's propyl,
and then on the second

00:05:28.990 --> 00:05:32.650
carbon, on the number two carbon
that we are attached

00:05:32.650 --> 00:05:36.720
to, you have a methyl group.

00:05:36.720 --> 00:05:37.970
So this is 1-methylpropyl.

00:05:42.370 --> 00:05:45.690
That's what each of these--
that's a 1-methypropyl and

00:05:45.690 --> 00:05:47.810
then that is a 1-methylpropyl.

00:05:47.810 --> 00:05:51.280
Another way to think about, an
isobutyl is the same thing as

00:05:51.280 --> 00:05:54.070
a 1-methylpropyl.

00:05:54.070 --> 00:05:58.330
This is the propyl part, and
then this right here-- let me

00:05:58.330 --> 00:06:00.250
do that in that color--
that right there

00:06:00.250 --> 00:06:01.780
is the methyl part.

00:06:01.780 --> 00:06:04.370
Oh, sorry, this isn't
a 1-methlypropyl.

00:06:04.370 --> 00:06:06.790
Let me be very careful
with my numbering.

00:06:06.790 --> 00:06:09.780
This is the one carbon, two
carbon, three carbon.

00:06:09.780 --> 00:06:12.090
The methyl comes off of
the second carbon.

00:06:12.090 --> 00:06:16.200
So this is a 2-methylpropyl:
one, two, three.

00:06:16.200 --> 00:06:18.400
Methyl comes off of
the second carbon.

00:06:18.400 --> 00:06:22.070
This is a 2-methylpropyl
group.

00:06:22.070 --> 00:06:24.620
And now when we look at it
alphabetically, methylpropyl

00:06:24.620 --> 00:06:28.550
still comes after cyclobutyl, so
it definitely won't change

00:06:28.550 --> 00:06:31.790
the numbering of things, and so
it still would be last. It

00:06:31.790 --> 00:06:33.480
also comes after cyclopropyl.

00:06:33.480 --> 00:06:37.360
If we were to do the systematic
naming, it would be

00:06:37.360 --> 00:06:42.040
1,6-dicyclo-- there's something
very strangely fun

00:06:42.040 --> 00:06:43.290
about this-- dicyclobutyl.

00:06:46.420 --> 00:06:49.670
Then you have your cyclopropyl,
7-cyclopropyl.

00:06:55.110 --> 00:06:56.960
It's like a secret code.

00:06:56.960 --> 00:06:59.200
And then you have your-- now,
this is interesting.

00:06:59.200 --> 00:07:01.340
You have two of these
guys, right?

00:07:01.340 --> 00:07:04.150
Now you don't say di- when you
have this kind of more complex

00:07:04.150 --> 00:07:06.000
naming or this systematic
naming.

00:07:06.000 --> 00:07:11.590
Instead you use the word
bis-, so we have bis-.

00:07:11.590 --> 00:07:13.790
So let me write it.

00:07:13.790 --> 00:07:21.930
We're at two and four,
2,4-bis, this thing.

00:07:21.930 --> 00:07:23.180
I can just bis-(2-methylpropyl).

00:07:33.540 --> 00:07:35.940
So this part right here
is the exact part as

00:07:35.940 --> 00:07:36.970
that part right there.

00:07:36.970 --> 00:07:37.990
This the common name.

00:07:37.990 --> 00:07:39.980
This is the systematic naming.

00:07:39.980 --> 00:07:41.250
And then we have our
cyclooctane.


Naming alkenes examples

WEBVTT
Kind: captions
Language: en

00:00:00.560 --> 00:00:03.590
Everything we've named so
far has been an alkane.

00:00:03.590 --> 00:00:05.630
We've seen all single bonds.

00:00:05.630 --> 00:00:08.610
Let's see if we can expand our
repertoire a little bit and do

00:00:08.610 --> 00:00:10.990
some alkenes.

00:00:10.990 --> 00:00:13.830
So let's look at this first
carbon chain right here.

00:00:13.830 --> 00:00:16.110
And actually, here I drew out
all of the hydrogens just to

00:00:16.110 --> 00:00:18.110
remind you that everything we
were doing before with just

00:00:18.110 --> 00:00:19.810
the lines, it really
was representing

00:00:19.810 --> 00:00:21.210
something like this.

00:00:21.210 --> 00:00:22.800
When you start having the
double bonds, and we'll

00:00:22.800 --> 00:00:25.020
explain it in more detail later
on, it actually starts

00:00:25.020 --> 00:00:27.400
to matter a little bit more to
draw the constituents, because

00:00:27.400 --> 00:00:29.550
there's actually different ways
that you can arrange it.

00:00:29.550 --> 00:00:31.750
Because these double bonds, you
can imagine, they're more

00:00:31.750 --> 00:00:34.610
rigid, you can't rotate
around them as much.

00:00:34.610 --> 00:00:37.050
But don't think about that
too much right now.

00:00:37.050 --> 00:00:38.830
Let's just try to name
these things.

00:00:38.830 --> 00:00:42.540
So like we always do, let's try
to find the longest chain

00:00:42.540 --> 00:00:43.070
of carbons.

00:00:43.070 --> 00:00:45.230
And there's only one chain
of carbons here.

00:00:45.230 --> 00:00:49.520
There's one, two, three, four,
five, six, seven carbons in

00:00:49.520 --> 00:00:50.170
that chain.

00:00:50.170 --> 00:00:54.460
So we're going to be
dealing with hept,

00:00:54.460 --> 00:00:55.930
that is seven carbons.

00:00:58.470 --> 00:01:00.700
But it's not going
to be a heptane.

00:01:00.700 --> 00:01:03.340
Heptane would mean that we
have all single bonds.

00:01:03.340 --> 00:01:07.250
Here we have a double bond, so
this is going to be an alkene.

00:01:07.250 --> 00:01:10.200
So this tells us right here
that we're dealing with an

00:01:10.200 --> 00:01:14.290
alkene, not an alkane.

00:01:14.290 --> 00:01:17.300
If you have a double bond,
it's an alkene.

00:01:17.300 --> 00:01:18.910
Triple bond, alkyne.

00:01:18.910 --> 00:01:21.000
We'll talk about that
in future videos.

00:01:21.000 --> 00:01:28.230
This is hept, and we'll put an
ene here, but we haven't

00:01:28.230 --> 00:01:31.040
specified where the double
bond is and we haven't

00:01:31.040 --> 00:01:32.790
numbered our carbons.

00:01:32.790 --> 00:01:35.730
When you see an alkene like
this, you start numbering

00:01:35.730 --> 00:01:40.300
closest to the double bond, just
like as if it was a alkyl

00:01:40.300 --> 00:01:43.340
group, as if it was a side
chain of carbons.

00:01:43.340 --> 00:01:46.860
So this side is closest to the
double bond, so let's start

00:01:46.860 --> 00:01:47.390
numbering there.

00:01:47.390 --> 00:01:54.180
One, two, three, four,
five, six, seven.

00:01:54.180 --> 00:01:57.710
The double bond is between two
and three, and to specify its

00:01:57.710 --> 00:01:59.830
location, you start at the
lowest of these numbers.

00:01:59.830 --> 00:02:02.620
So this double bond is at two.

00:02:02.620 --> 00:02:03.870
This is actually hept-2-ene.

00:02:06.530 --> 00:02:10.330
So this tells us that we have a
seven carbon chain that has

00:02:10.330 --> 00:02:14.060
a double bond starting-- the
ene tells us a double bond.

00:02:14.060 --> 00:02:15.080
Let me write that down.

00:02:15.080 --> 00:02:17.940
So this double bond right
there, that's what

00:02:17.940 --> 00:02:19.190
the ene tells us.

00:02:21.710 --> 00:02:25.910
Double bond between two carbons,
it's an alkene.

00:02:25.910 --> 00:02:28.120
The double bond starts-- if you
start at this point-- the

00:02:28.120 --> 00:02:31.000
double bond starts at number two
carbon, and then it will

00:02:31.000 --> 00:02:33.620
go to the number three carbon.

00:02:33.620 --> 00:02:37.960
Now you might be asking, well,
what if I had more than one

00:02:37.960 --> 00:02:38.830
double bond here?

00:02:38.830 --> 00:02:41.630
So let me draw a quick
example of that.

00:02:41.630 --> 00:02:45.760
Let's say I have something like,
one, two, three, four,

00:02:45.760 --> 00:02:47.060
five, six, seven.

00:02:47.060 --> 00:02:49.010
So this is the same
molecule again.

00:02:49.010 --> 00:02:51.120
One, two, three, four,
five, six, seven.

00:02:51.120 --> 00:02:53.810
The way we drew it up
here, it would look

00:02:53.810 --> 00:02:55.130
something like this.

00:02:55.130 --> 00:03:00.170
What if I had another double
bond sitting right here?

00:03:00.170 --> 00:03:02.170
How would we specify this?

00:03:02.170 --> 00:03:05.220
Well, once again we have
seven carbons.

00:03:05.220 --> 00:03:07.860
One, two, three, four,
five, six, seven.

00:03:07.860 --> 00:03:10.580
So we're still going to
have a hept here.

00:03:10.580 --> 00:03:12.850
It's still going to
be an alkene, so

00:03:12.850 --> 00:03:15.310
we put our ene here.

00:03:15.310 --> 00:03:17.740
But we start numbering it, once
again, closest to the

00:03:17.740 --> 00:03:18.970
closest double bond.

00:03:18.970 --> 00:03:25.070
So one, two, three, four,
five, six, seven.

00:03:25.070 --> 00:03:27.620
But now we have a double bond
starting at two to three, so

00:03:27.620 --> 00:03:28.940
it would be hept-2.

00:03:28.940 --> 00:03:31.405
And we also have another double
bond starting from four

00:03:31.405 --> 00:03:32.760
and going to five,
so hept-2,4-ene.

00:03:35.920 --> 00:03:38.290
That's what this molecule
right there is.

00:03:38.290 --> 00:03:41.560
Sometimes, this is the-- I
guess-- proper naming, but

00:03:41.560 --> 00:03:43.610
just so you're familiar with
it if you ever see it.

00:03:43.610 --> 00:03:46.620
Sometimes someone would write
hept-2-ene, they'll write that

00:03:46.620 --> 00:03:51.390
as 2-heptene, probably because
it's easier to say 2-heptene.

00:03:51.390 --> 00:03:53.710
And from this, you would be able
to draw this thing over

00:03:53.710 --> 00:03:55.620
here, so it's giving you the
same amount of information.

00:03:55.620 --> 00:03:58.390
Similarly over here, they
might say 2,4-heptene.

00:03:58.390 --> 00:04:01.520
But this is the specific,
this is the correct

00:04:01.520 --> 00:04:02.640
way to write it.

00:04:02.640 --> 00:04:04.890
It let's you know the two and
the four apply to the ene,

00:04:04.890 --> 00:04:06.860
which you know applies
to double bonds.

00:04:06.860 --> 00:04:09.000
Let's do a couple more.

00:04:09.000 --> 00:04:13.910
So over here, I have a double
bond, and I also have some

00:04:13.910 --> 00:04:14.720
side chains.

00:04:14.720 --> 00:04:17.140
Let's see if we can figure
out how to deal with

00:04:17.140 --> 00:04:18.519
all of these things.

00:04:18.519 --> 00:04:22.300
So first of all, what is our
longest chain of carbons?

00:04:22.300 --> 00:04:26.400
So we have one, two, three,
four, five, six.

00:04:26.400 --> 00:04:28.180
Now we could go in either
direction, it doesn't matter.

00:04:28.180 --> 00:04:30.650
Seven carbons or
seven carbons.

00:04:30.650 --> 00:04:33.580
Let's start numbering closest
to the double bond.

00:04:33.580 --> 00:04:37.490
The double bond actually will
take precedence over any other

00:04:37.490 --> 00:04:39.210
groups that are attached
to it.

00:04:39.210 --> 00:04:41.990
So let's take precedence--
well, over any other

00:04:41.990 --> 00:04:42.940
groups in this case.

00:04:42.940 --> 00:04:45.510
There will be other groups that
will take precedence in

00:04:45.510 --> 00:04:46.800
the future.

00:04:46.800 --> 00:04:50.580
But the double bond takes
precedence over this side

00:04:50.580 --> 00:04:52.300
chain, this methyl group.

00:04:52.300 --> 00:04:54.230
But it doesn't matter in this
case, we'd want to start

00:04:54.230 --> 00:04:55.140
numbering at this end.

00:04:55.140 --> 00:04:59.800
It's one, two carbon, three
carbon, four carbon, five

00:04:59.800 --> 00:05:02.100
carbon, six carbon,
seven carbon.

00:05:02.100 --> 00:05:03.855
So we're dealing with
a hept again.

00:05:08.610 --> 00:05:12.480
We have a double bond starting
from the second carbon to the

00:05:12.480 --> 00:05:13.760
third carbon.

00:05:13.760 --> 00:05:16.750
So this thing right here, this
double bond from the second

00:05:16.750 --> 00:05:17.760
carbon to the third carbon.

00:05:17.760 --> 00:05:23.880
So it's hept-2,3-ene-- sorry,
not 2,3, 2-ene.

00:05:23.880 --> 00:05:26.490
You don't write both
endpoints.

00:05:26.490 --> 00:05:28.420
If there was a three, then there
would have been another

00:05:28.420 --> 00:05:29.530
double bond there.

00:05:29.530 --> 00:05:30.780
It's hept-2-ene.

00:05:33.140 --> 00:05:35.680
And then we have this methyl
group here, which is also

00:05:35.680 --> 00:05:37.900
sitting on the second carbon.

00:05:37.900 --> 00:05:44.040
So this methyl group right there
on the second carbon.

00:05:44.040 --> 00:05:45.290
So we would say
2-methyl-hept-2-ene.

00:05:52.050 --> 00:05:55.020
It's a hept-2-ene, that's all of
this part over here, double

00:05:55.020 --> 00:05:56.380
bonds starting on
the two if we're

00:05:56.380 --> 00:05:57.570
numbering from the right.

00:05:57.570 --> 00:05:59.870
And then the methyl group
is also attached

00:05:59.870 --> 00:06:02.260
to that second carbon.

00:06:02.260 --> 00:06:04.960
Let's do one more of these.

00:06:04.960 --> 00:06:08.830
So we have a cycle here, and
once again the root is going

00:06:08.830 --> 00:06:11.890
to be the largest chain or
the largest ring here.

00:06:11.890 --> 00:06:15.110
Our main ring is the largest
one, and we have one, two,

00:06:15.110 --> 00:06:18.150
three, four, five,
six, carbon.

00:06:18.150 --> 00:06:24.890
So we are dealing with hex as
our root for kind of the core

00:06:24.890 --> 00:06:26.350
of our structure.

00:06:26.350 --> 00:06:29.240
It's in a cycle, so it's
going to be cyclohex.

00:06:29.240 --> 00:06:30.230
So let me write that.

00:06:30.230 --> 00:06:32.980
So it's going to be cyclohex.

00:06:32.980 --> 00:06:35.280
But it has a double
bond in it.

00:06:35.280 --> 00:06:41.710
So it's cyclohex ene,
cyclohexene.

00:06:41.710 --> 00:06:43.040
Let me do this in a
different color.

00:06:43.040 --> 00:06:45.750
So we have this double bond
here, and that's why we know

00:06:45.750 --> 00:06:47.410
it is an ene.

00:06:47.410 --> 00:06:49.160
Now you're probably saying, Hey
Sal, how come we didn't

00:06:49.160 --> 00:06:50.850
have to number where
the ene is?

00:06:50.850 --> 00:06:56.990
So if you only have one double
bond in a ring, it's assumed

00:06:56.990 --> 00:07:01.380
that one end point of the double
bond is your 1-carbon.

00:07:01.380 --> 00:07:05.200
When you write just cyclohexene,
you know-- so

00:07:05.200 --> 00:07:07.100
cyclohexene would look
just like this.

00:07:10.590 --> 00:07:11.480
Just like that.

00:07:11.480 --> 00:07:13.140
You don't have to specify
where it is.

00:07:13.140 --> 00:07:15.390
It's just, one of these are
going to be the double bond.

00:07:15.390 --> 00:07:17.920
Now when you have other
constituents on it, by

00:07:17.920 --> 00:07:21.510
definition or I guess the proper
naming mechanism, is

00:07:21.510 --> 00:07:23.940
one of the endpoints of the
double bond will be the

00:07:23.940 --> 00:07:27.070
1-carbon, and if any of those
endpoints have something else

00:07:27.070 --> 00:07:29.730
on it, that will definitely
be the 1-carbon.

00:07:29.730 --> 00:07:33.270
So these both are kind of the
candidates for the 1-carbon,

00:07:33.270 --> 00:07:36.640
but this point right here also
has this methyl group.

00:07:36.640 --> 00:07:40.020
We will start numbering there,
one, and then you want to

00:07:40.020 --> 00:07:43.580
number in the direction of the
other side of the double bond.

00:07:43.580 --> 00:07:48.470
One, two, three, four,
five, six.

00:07:48.470 --> 00:07:51.750
So we have three methyl
groups, one on one.

00:07:51.750 --> 00:07:54.490
So these are the-- let me circle
the methyl groups.

00:07:54.490 --> 00:07:55.950
That's a methyl group
right there.

00:07:55.950 --> 00:07:57.490
That's a methyl group
right there.

00:07:57.490 --> 00:07:59.470
That's just one carbon.

00:07:59.470 --> 00:08:01.760
So we have three methyl groups,
so this is going to

00:08:01.760 --> 00:08:05.650
be-- it's at the one, the
four, and the six.

00:08:05.650 --> 00:08:06.900
So it is 1, 4, 6.

00:08:09.370 --> 00:08:19.030
We have three methyl groups, so
it's trimethyl cyclohexene.

00:08:19.030 --> 00:08:21.460
1, 4, 6-trimethylcyclohexene.

00:08:21.460 --> 00:08:25.720
That's what that is, hopefully
you found that useful.


Organic chemistry naming examples 4

WEBVTT
Kind: captions
Language: en

00:00:00.570 --> 00:00:03.110
We've done a bunch of examples
looking at the actual

00:00:03.110 --> 00:00:06.070
molecular structure and trying
to come up with the name.

00:00:06.070 --> 00:00:07.960
In this video, we'll go
the other way around.

00:00:07.960 --> 00:00:11.020
We'll start with the name and
see if we can actually draw

00:00:11.020 --> 00:00:14.810
the molecular structure of
whatever this might be.

00:00:14.810 --> 00:00:15.530
So let's start.

00:00:15.530 --> 00:00:17.400
When you first look at these,
it's very daunting, but you

00:00:17.400 --> 00:00:19.970
always want to start really at
the end, so you know what kind

00:00:19.970 --> 00:00:21.930
of the core of the structure
is going to be.

00:00:21.930 --> 00:00:24.790
So if you look at the end of
this, you have an -ane, so

00:00:24.790 --> 00:00:26.915
there's not going to be any
double or triple bonds here.

00:00:26.915 --> 00:00:28.350
It's all single bonds.

00:00:28.350 --> 00:00:33.790
It's a hexadecane, so let's
think about that.

00:00:33.790 --> 00:00:38.170
Hexadec-, that's six and ten.

00:00:38.170 --> 00:00:42.520
Hexadec- was a prefix for
16, so this is 16

00:00:42.520 --> 00:00:50.640
single-bonded carbons.

00:00:50.640 --> 00:01:01.150
And cyclohexadecane, so 16
single-bonded carbons in a

00:01:01.150 --> 00:01:03.680
ring, so this part
of it right here.

00:01:03.680 --> 00:01:04.440
So let me just do this.

00:01:04.440 --> 00:01:09.730
So cyclohexadecane, let's draw
that part first. It's not easy

00:01:09.730 --> 00:01:15.480
to draw even a 16-carbon ring,
so let's start here.

00:01:15.480 --> 00:01:31.790
One, two, three, four, five,
six, seven, eight, nine, ten,

00:01:31.790 --> 00:01:39.130
eleven, twelve, thirteen,
fourteen,

00:01:39.130 --> 00:01:42.550
fifteen, and then sixteen.

00:01:42.550 --> 00:01:43.230
I think I got it.

00:01:43.230 --> 00:01:45.400
Let me count them again and
then I can connect them up

00:01:45.400 --> 00:01:45.970
into cycles.

00:01:45.970 --> 00:01:50.120
It's one, two, three, four,
five, six, seven, eight, nine,

00:01:50.120 --> 00:01:53.900
ten, eleven, twelve, thirteen,
fourteen, fifteen, sixteen.

00:01:53.900 --> 00:01:57.690
All right, I drew the
cyclohexadecane part.

00:01:57.690 --> 00:02:00.710
Now, if we go back a little,
let's see, we have a

00:02:00.710 --> 00:02:01.960
2,9-diisopropyl.

00:02:04.250 --> 00:02:04.930
What does this mean?

00:02:04.930 --> 00:02:07.970
This means that we have an
isopropyl at the two

00:02:07.970 --> 00:02:09.940
and the nine spot.

00:02:09.940 --> 00:02:13.690
Now when you are drawing the
structure from the name, you

00:02:13.690 --> 00:02:16.780
could just arbitrarily on
someplace on this ring pick

00:02:16.780 --> 00:02:19.420
what your one through your
sixteen spots are.

00:02:19.420 --> 00:02:22.830
I'll just arbitrarily pick them,
because I could have

00:02:22.830 --> 00:02:24.540
drawn this ring any which way.

00:02:24.540 --> 00:02:32.420
One, two, three, four, five,
six, seven, eight, nine, ten,

00:02:32.420 --> 00:02:39.550
eleven, twelve, thirteen,
fourteen, fifteen, sixteen.

00:02:39.550 --> 00:02:42.770
All right, so this next
piece right here, let

00:02:42.770 --> 00:02:44.390
me do this in magenta.

00:02:44.390 --> 00:02:48.820
2,9-diisopropyl, this is telling
us that at spot number

00:02:48.820 --> 00:02:53.660
two and at spot number nine,
I have isopropyl.

00:02:53.660 --> 00:02:56.650
The di- is just saying I have
two isopropyls at two and

00:02:56.650 --> 00:02:58.750
nine, so you can kind
of ignore the di-.

00:02:58.750 --> 00:03:01.240
I have an isopropyl, and you may
or may not remember that

00:03:01.240 --> 00:03:02.680
an isopropyl looks like this.

00:03:02.680 --> 00:03:08.020
It's three carbons, so it's
going to be one, two, three,

00:03:08.020 --> 00:03:11.640
and the connection point to the
main ring in this case is

00:03:11.640 --> 00:03:13.120
going to be in the middle
carbon, so it

00:03:13.120 --> 00:03:14.180
kind of forms a Y.

00:03:14.180 --> 00:03:17.820
All of the isos, the isopropyl,
isobutyl, they all

00:03:17.820 --> 00:03:21.840
look like Y's, so it's going to
be linked right over here.

00:03:24.620 --> 00:03:27.550
That's also going to happen at
the ninth carbon, so at the

00:03:27.550 --> 00:03:30.550
ninth carbon we're going to
have another isopropyl.

00:03:30.550 --> 00:03:34.750
We're going to have another
isopropyl at the ninth carbon.

00:03:34.750 --> 00:03:37.970
All right, we've taken care
of the 2,9-isopropyl.

00:03:37.970 --> 00:03:44.840
Then we have the 6-ethyl, which
is just a two carbon.

00:03:44.840 --> 00:03:49.740
Remember, meth- is one, eth-
is two, prop- is three.

00:03:49.740 --> 00:03:51.780
Let me write this down.

00:03:51.780 --> 00:03:56.600
So this is going to be prop-
is equal to three.

00:03:56.600 --> 00:04:04.240
Isoprop- is equal to that type
of shape right over there.

00:04:04.240 --> 00:04:10.760
In this case, eth- is equal to
two, so it's a 6-ethyl group.

00:04:10.760 --> 00:04:15.380
So at six we have an ethyl
group, so one, two, carbons,

00:04:15.380 --> 00:04:19.930
and it's connected at the six
carbon on the main ring.

00:04:19.930 --> 00:04:21.190
And then finally we have
a cyclopentyl.

00:04:24.800 --> 00:04:29.950
So if we look at-- let me find
a color I haven't used yet--

00:04:29.950 --> 00:04:30.700
cyclopentyl.

00:04:30.700 --> 00:04:35.080
so pent- is five, but it's five
in a cycle, so this is a

00:04:35.080 --> 00:04:37.160
five-carbon ring that's
branching

00:04:37.160 --> 00:04:38.090
off of the main ring.

00:04:38.090 --> 00:04:40.800
It's at the first spot.

00:04:40.800 --> 00:04:44.940
Let me draw a five-carbon rings,
so pent- is equal to

00:04:44.940 --> 00:04:48.410
five, so it would look
like this, one: two,

00:04:48.410 --> 00:04:50.285
three, four, five.

00:04:50.285 --> 00:04:52.140
It looks just like a pentagon.

00:04:52.140 --> 00:04:55.640
That's a cyclopentyl group and
it's attached to the one

00:04:55.640 --> 00:04:59.190
carbon on my cyclohexadecane,
so it is

00:04:59.190 --> 00:05:01.370
attached just like that.

00:05:01.370 --> 00:05:01.840
We're done.

00:05:01.840 --> 00:05:02.680
We've drawn 1-cyclopentyl-6-
ethyl-2,9-diisop

00:05:02.680 --> 00:05:03.930
ropylcyclohexadecane.

00:05:07.440 --> 00:05:09.590
Let's do another one.

00:05:09.590 --> 00:05:11.360
I think we're getting
the hang of it.

00:05:11.360 --> 00:05:15.380
So here, maybe we can do this
one a little bit faster.

00:05:15.380 --> 00:05:19.180
Let's see, we have a
tetramethyldodecane, so the

00:05:19.180 --> 00:05:23.320
main root here is the
dodecane, do- for

00:05:23.320 --> 00:05:24.650
two, dec- for ten.

00:05:24.650 --> 00:05:26.210
This is a 12-carbon chain.

00:05:26.210 --> 00:05:29.310
It's not in a cycle, so let
me just draw it out.

00:05:29.310 --> 00:05:36.180
We have one, two, three, four,
five, six, seven, eight, nine,

00:05:36.180 --> 00:05:39.930
ten, eleven, twelve, and so
we can just number them

00:05:39.930 --> 00:05:41.510
arbitrarily, just because
I could have drawn

00:05:41.510 --> 00:05:42.160
this any which way.

00:05:42.160 --> 00:05:50.200
So it's one, two, three, four,
five, six, seven, eight, nine,

00:05:50.200 --> 00:05:52.860
ten, eleven, twelve.

00:05:52.860 --> 00:05:55.600
That's the dodecane,
all single bonds.

00:05:55.600 --> 00:05:58.960
Then we have a
3,6,9,9-tetramethyl.

00:05:58.960 --> 00:06:02.565
All this is telling us--
remember, meth- is one carbon,

00:06:02.565 --> 00:06:05.520
so all this is telling us is
at the three, the six, the

00:06:05.520 --> 00:06:11.150
nine, so at the three, the six
and twice at the nine spot, we

00:06:11.150 --> 00:06:13.520
have methyl groups, and we
have four methyl groups.

00:06:13.520 --> 00:06:15.070
That's all the tetramethyl
is saying so it's

00:06:15.070 --> 00:06:15.800
a little bit redundant.

00:06:15.800 --> 00:06:18.820
We know we have four of
them here: 3,6,9,9.

00:06:18.820 --> 00:06:22.270
We have methyl groups at
each of those places.

00:06:22.270 --> 00:06:26.990
We have one methyl group at
three, and then that is bonded

00:06:26.990 --> 00:06:29.590
with the third carbon on
the dodecane chain.

00:06:29.590 --> 00:06:33.570
We have one at six bonded
to the six carbon on

00:06:33.570 --> 00:06:34.540
the dodecane chain.

00:06:34.540 --> 00:06:39.320
We have two at nine, so that's
one at nine and then we have

00:06:39.320 --> 00:06:42.130
another one at nine bonded
to the nine carbon on the

00:06:42.130 --> 00:06:43.100
dodecane chain.

00:06:43.100 --> 00:06:43.890
And we're done.

00:06:43.890 --> 00:06:44.590
That's it.

00:06:44.590 --> 00:06:45.840
That's 3,6,9,9-
tetramethyldodecane.

00:06:48.450 --> 00:06:51.480
Let's do another one.

00:06:51.480 --> 00:06:52.730
1,3-bis(1,1-dime
thylethyl)cyclopentane.

00:06:58.050 --> 00:07:01.080
So once again, just kind
of breathe slowly.

00:07:01.080 --> 00:07:04.230
It's very daunting right when
you look at it, but just start

00:07:04.230 --> 00:07:06.670
with the core: cyclopentane.

00:07:06.670 --> 00:07:09.185
That's just a simple
five-carbon ring.

00:07:09.185 --> 00:07:12.290
A five carbon ring that looks
like a pentagon: one, two,

00:07:12.290 --> 00:07:17.270
three, four, five.

00:07:19.910 --> 00:07:21.060
There you go.

00:07:21.060 --> 00:07:22.650
That is a five-carbon ring.

00:07:22.650 --> 00:07:26.220
We can number it however we
want, so one, two, three,

00:07:26.220 --> 00:07:28.290
four, and five.

00:07:28.290 --> 00:07:35.260
This is telling us at the one
and the three position we

00:07:35.260 --> 00:07:37.360
have-- and the bis- is
kind of redundant.

00:07:37.360 --> 00:07:38.810
This is saying we have
two of these things.

00:07:38.810 --> 00:07:39.560
Obviously, we have two.

00:07:39.560 --> 00:07:40.990
We have one at the one
and one at the three.

00:07:40.990 --> 00:07:42.250
So you can kind of
ignore the bis-.

00:07:42.250 --> 00:07:43.600
That's just the convention
and we've seen

00:07:43.600 --> 00:07:44.740
that multiple times.

00:07:44.740 --> 00:07:46.440
But at each of those positions,
we have a

00:07:46.440 --> 00:07:47.690
1,1-dimethylethyl.

00:07:49.370 --> 00:07:51.800
So what's a dimethylethyl
look like?

00:07:51.800 --> 00:07:53.830
So let's think about
it a little bit.

00:07:53.830 --> 00:07:57.280
Let's think about it and
let me do it orange.

00:07:57.280 --> 00:08:00.860
They obviously named it using
systematic naming and what we

00:08:00.860 --> 00:08:03.960
have here, we have an ethyl
as kind of the core

00:08:03.960 --> 00:08:05.650
of this side chain.

00:08:05.650 --> 00:08:09.620
So if an ethyl is equal to two
carbons, so this is two

00:08:09.620 --> 00:08:10.970
carbons right there.

00:08:10.970 --> 00:08:15.320
So let me draw a two
carbon: one, two.

00:08:15.320 --> 00:08:18.140
That is two carbons
right over there.

00:08:18.140 --> 00:08:19.820
I'm just drawing it
at the three spot.

00:08:19.820 --> 00:08:21.700
I'll draw it also at the
one spot, actually.

00:08:21.700 --> 00:08:23.630
So that is two carbons
right there.

00:08:23.630 --> 00:08:24.970
That's the ethyl part.

00:08:24.970 --> 00:08:27.380
And then on 1,1, so if we number
them, we number where

00:08:27.380 --> 00:08:31.330
it's connected, so
it's one, two.

00:08:31.330 --> 00:08:33.179
This is saying 1,1-dimethyl.

00:08:33.179 --> 00:08:36.570
So on this ethyl chain,
you have two methyls.

00:08:36.570 --> 00:08:40.690
Remember, methyl is equal to
one, so this is one carbon.

00:08:40.690 --> 00:08:41.809
You have one carbon.

00:08:41.809 --> 00:08:44.600
That's what methyl is, but
you have two of them.

00:08:44.600 --> 00:08:45.950
You have dimethyl.

00:08:45.950 --> 00:08:47.760
You have it twice
at the one spot.

00:08:47.760 --> 00:08:50.550
So you have one methyl here
and then you have another

00:08:50.550 --> 00:08:51.140
methyl there.

00:08:51.140 --> 00:08:51.910
Same thing over here.

00:08:51.910 --> 00:08:54.090
You have 1-methyl on the one
spot and then you have another

00:08:54.090 --> 00:08:55.750
1-methyl on the one spot.

00:08:55.750 --> 00:09:00.110
And then you are connected at
positions one and positions

00:09:00.110 --> 00:09:03.940
three, so you're connected there
and you are connected

00:09:03.940 --> 00:09:05.290
right over there.

00:09:05.290 --> 00:09:06.930
And you're done, That's it.

00:09:06.930 --> 00:09:08.560
That is our structure.

00:09:08.560 --> 00:09:12.970
Now, if you did this with common
naming, instead of this

00:09:12.970 --> 00:09:15.880
group being a 1,1-dimethylethyl,
you might

00:09:15.880 --> 00:09:18.120
see that we're connected to
a group that has one, two,

00:09:18.120 --> 00:09:20.170
three, four carbons in it.

00:09:20.170 --> 00:09:22.520
The carbon that we're connected
to branches off to

00:09:22.520 --> 00:09:23.415
three other carbons.

00:09:23.415 --> 00:09:25.960
It is a tert-butyl.

00:09:25.960 --> 00:09:30.450
So you can also call
this a 1,3-- let me

00:09:30.450 --> 00:09:31.390
just write it down.

00:09:31.390 --> 00:09:39.100
So another name for this would
be 1,3-tert-- or sometimes

00:09:39.100 --> 00:09:48.070
people just write a t there--
t-butylcyclo-- no, actually I

00:09:48.070 --> 00:09:51.890
should say di-t-butyl, because
we have two of them.

00:09:51.890 --> 00:09:53.140
1,3-di-t-butylcyclopentane.


Organic chemistry naming examples 3

WEBVTT
Kind: captions
Language: en

00:00:00.490 --> 00:00:03.960
We've got a few more molecular
structures to name, so let's

00:00:03.960 --> 00:00:05.980
look at this first
one right here.

00:00:05.980 --> 00:00:08.840
The first thing you always want
to do is identify the

00:00:08.840 --> 00:00:09.730
longest chain.

00:00:09.730 --> 00:00:14.030
If we start over here, we have
one, two, three, four, five,

00:00:14.030 --> 00:00:19.260
six, seven, eight, nine, ten,
eleven, twelve, thirteen

00:00:19.260 --> 00:00:21.050
carbons, looks pretty long.

00:00:21.050 --> 00:00:22.040
Now what if we start
over here?

00:00:22.040 --> 00:00:25.240
This looks like it could also
be a long chain: one, two,

00:00:25.240 --> 00:00:29.900
three, four, five, six, seven,
eight, nine, ten, eleven,

00:00:29.900 --> 00:00:31.600
twelve, thirteen.

00:00:31.600 --> 00:00:34.180
So we have two different chains,
depending on whether

00:00:34.180 --> 00:00:36.730
we want to go up here or whether
we go over here, that

00:00:36.730 --> 00:00:38.520
have a length of thirteen.

00:00:38.520 --> 00:00:42.340
So you're probably asking, which
chain do you choose?

00:00:42.340 --> 00:00:45.360
You should always, if we have
two chains of equal lengths

00:00:45.360 --> 00:00:47.860
and they're the longest chains,
you pick the one that

00:00:47.860 --> 00:00:52.690
will have more branches or
more alkyl groups on it.

00:00:52.690 --> 00:00:56.250
So this group right here, if we
pick this from here to here

00:00:56.250 --> 00:00:58.560
as our chain, we only have
one group on it,

00:00:58.560 --> 00:00:59.830
that group up there.

00:00:59.830 --> 00:01:02.970
If we pick this chain, starting
over here and then

00:01:02.970 --> 00:01:05.550
going over here, we have
two groups on it.

00:01:05.550 --> 00:01:10.250
We would have this group over
here and then we would have

00:01:10.250 --> 00:01:14.140
this group over here.

00:01:14.140 --> 00:01:16.540
This is the better chain
to use because it has

00:01:16.540 --> 00:01:17.730
more groups on it.

00:01:17.730 --> 00:01:19.110
It has more groups,
but the groups

00:01:19.110 --> 00:01:21.100
are smaller and simpler.

00:01:21.100 --> 00:01:22.550
So let's start counting.

00:01:22.550 --> 00:01:25.010
And the direction we want to
count, we always want to start

00:01:25.010 --> 00:01:27.980
on the side of the chain where
we're going to encounter

00:01:27.980 --> 00:01:31.060
something first, and everything
is closer this end

00:01:31.060 --> 00:01:35.090
of the chain so we'll
start counting here.

00:01:35.090 --> 00:01:45.530
One, two, three, four, five,
six, seven, eight, nine, ten,

00:01:45.530 --> 00:01:50.870
eleven, twelve, thirteen, so
we have thirteen carbons on

00:01:50.870 --> 00:01:51.650
our main chain.

00:01:51.650 --> 00:01:52.880
Let me draw our main chain.

00:01:52.880 --> 00:01:56.830
So our main chain is this thing
in orange I'm drawing

00:01:56.830 --> 00:01:57.320
right here.

00:01:57.320 --> 00:02:01.640
That is our main chain.

00:02:01.640 --> 00:02:04.220
Thirteen, that's
three and ten.

00:02:04.220 --> 00:02:08.380
The prefix is tridec- and it's
tridecane because we have all

00:02:08.380 --> 00:02:11.960
single bonds here, so
it's tridecane.

00:02:11.960 --> 00:02:16.360
Tridecane is the main chain.

00:02:16.360 --> 00:02:18.200
Then we have two groups
over here.

00:02:18.200 --> 00:02:21.650
This one in green, this only has
one the carbon branching

00:02:21.650 --> 00:02:25.070
off of the main chain, so it's
prefix will be meth- and it'll

00:02:25.070 --> 00:02:30.310
be a methyl group, so
that is methyl.

00:02:30.310 --> 00:02:33.560
That is a methyl group
right there.

00:02:33.560 --> 00:02:37.980
Then this one down here, we have
one, two, three carbons.

00:02:37.980 --> 00:02:41.200
the prefix is prop-, so this
is a propyl group.

00:02:46.990 --> 00:02:53.660
And the methyl is sitting on the
three carbon of our main

00:02:53.660 --> 00:02:57.920
chain and the propyl group is
sitting on the four carbon:

00:02:57.920 --> 00:02:59.590
one, two, three, four.

00:02:59.590 --> 00:03:02.370
Now when we figure out what
order to list them in when we

00:03:02.370 --> 00:03:04.830
actually write out the name,
M, we just do it in

00:03:04.830 --> 00:03:06.270
alphabetical order.

00:03:06.270 --> 00:03:11.720
M comes before P, so we right
3-methyl before 4-propyl.

00:03:11.720 --> 00:03:16.540
The entire compound here is
or the entire molecule is

00:03:16.540 --> 00:03:33.540
3-methyl-4-propyltridecane And
this is actually all going to

00:03:33.540 --> 00:03:34.520
be one word.

00:03:34.520 --> 00:03:37.250
You use dashes to separate when
you have numbers, but if

00:03:37.250 --> 00:03:38.860
you have a word followed by
a word, it just becomes

00:03:38.860 --> 00:03:42.530
propyltridecane, so
3-methyl-4-propyltridecane.

00:03:42.530 --> 00:03:43.530
And we're done.

00:03:43.530 --> 00:03:44.710
Let's do this one down here.

00:03:44.710 --> 00:03:47.090
Now this one seems a little
bit more complex.

00:03:47.090 --> 00:03:49.510
The first thing to see is what
is the largest chain or the

00:03:49.510 --> 00:03:53.280
largest ring that we have
in our structure?

00:03:53.280 --> 00:03:55.910
The two candidates, we have
this chain over here.

00:03:55.910 --> 00:03:59.030
This has one, two, three, four,

00:03:59.030 --> 00:04:02.590
five, six, seven carbons.

00:04:02.590 --> 00:04:04.930
Let's see how many carbons
our ring has.

00:04:04.930 --> 00:04:13.140
Our ring has one, two, three,
four, five, six, seven, eight,

00:04:13.140 --> 00:04:14.190
nine carbons.

00:04:14.190 --> 00:04:18.290
So the ring is the largest
core structure in this

00:04:18.290 --> 00:04:22.390
molecule, so that will be
our core structure.

00:04:22.390 --> 00:04:27.200
We have nine carbons-- let me
highlight it-- so the ring is

00:04:27.200 --> 00:04:28.896
this right here.

00:04:28.896 --> 00:04:30.620
It has nine carbons.

00:04:30.620 --> 00:04:33.260
The prefix for nine is non-.

00:04:33.260 --> 00:04:37.290
It's all single bonds, so it's
nonane, and it is in a cycle.

00:04:37.290 --> 00:04:39.420
It's a ring, so it's
cyclononane.

00:04:39.420 --> 00:04:42.070
This part right here, that
part right there, is

00:04:42.070 --> 00:04:43.320
cyclononane.

00:04:46.850 --> 00:04:50.970
We have several things that
branch off of the cyclononane,

00:04:50.970 --> 00:04:53.010
so let's look at them one at a
time, and then we'll think

00:04:53.010 --> 00:04:56.070
about how we're going to number
them on the ring.

00:04:56.070 --> 00:04:59.090
We looked already at this at
this chain that has seven

00:04:59.090 --> 00:05:10.520
carbons: one, two, three,
four, five, six, seven.

00:05:10.520 --> 00:05:12.150
So that is a heptyl group.

00:05:16.100 --> 00:05:18.650
This over here, let's see
what we're dealing with.

00:05:18.650 --> 00:05:23.570
We have one, two, three carbons,
so that is just a

00:05:23.570 --> 00:05:25.170
standard propyl group.

00:05:29.450 --> 00:05:37.540
Then here, we have one, two,
three, four carbons, so we

00:05:37.540 --> 00:05:39.410
could say this is
a butyl group.

00:05:39.410 --> 00:05:40.960
But this isn't just
any butyl group.

00:05:40.960 --> 00:05:44.360
If we use the common naming,
the carbon we immediately

00:05:44.360 --> 00:05:46.760
touch on or that we immediately
get to when we go

00:05:46.760 --> 00:05:51.030
off of our main ring, that
branches off into three other

00:05:51.030 --> 00:05:55.000
carbons, so this is tert-,
tert- for three.

00:05:55.000 --> 00:05:56.620
The tert- is usually
written in italics.

00:05:56.620 --> 00:05:59.140
It's hard to differentiate
that when you see it.

00:05:59.140 --> 00:06:02.470
I'll write it in cursive.

00:06:02.470 --> 00:06:03.810
This is tert.

00:06:03.810 --> 00:06:07.260
This is a tertbutyl group.

00:06:07.260 --> 00:06:10.090
Now, the next question is how
do we specify where these

00:06:10.090 --> 00:06:14.070
different groups sit
on this main ring?

00:06:14.070 --> 00:06:17.500
If you just had one group, you
wouldn't have to specify it,

00:06:17.500 --> 00:06:19.930
but when you have more than one,
what you actually do is

00:06:19.930 --> 00:06:22.900
you figure out which one would
be alphabetically first, and

00:06:22.900 --> 00:06:24.990
that would be number one.

00:06:24.990 --> 00:06:28.860
Now, we have an H in heptyl, a
P in propyl, and tert-butyl,

00:06:28.860 --> 00:06:31.250
you might say, well, do I use
the T or do I use the B?

00:06:31.250 --> 00:06:33.770
And this is just the convention,
you use the B.

00:06:33.770 --> 00:06:36.790
If you have sec-butyl or
tert-butyl, you ignore the

00:06:36.790 --> 00:06:37.980
sec- or the tert-.

00:06:37.980 --> 00:06:41.190
If this was an isobutyl or an
isopropyl, you actually would

00:06:41.190 --> 00:06:44.200
use the I, so it's a little
bit-- I guess the best way to

00:06:44.200 --> 00:06:45.800
think about it is there's a dash
here so you can kind of

00:06:45.800 --> 00:06:47.990
ignore it, but if this was
isobutyl it would all be one

00:06:47.990 --> 00:06:49.940
word, so you would
consider the I.

00:06:49.940 --> 00:06:53.830
So in this situation, we would
consider the B, and B comes

00:06:53.830 --> 00:06:57.200
before P or an H, so that
is where we will

00:06:57.200 --> 00:06:59.410
start numbering one.

00:06:59.410 --> 00:07:01.580
Then to figure out which
direction to keep numbering

00:07:01.580 --> 00:07:04.360
in, we just go in the direction
where we're likely

00:07:04.360 --> 00:07:06.360
to encounter the first or where
we will encounter the

00:07:06.360 --> 00:07:10.180
first side chain, so we'll go
in this direction because we

00:07:10.180 --> 00:07:11.240
get right to the propyl group.

00:07:11.240 --> 00:07:19.440
One, two, three, four, five,
six, seven, eight, nine.

00:07:19.440 --> 00:07:21.180
So this compound, we're going
to start with the

00:07:21.180 --> 00:07:24.430
alphabetically first side chain,
so it's 1-tert-butyl.

00:07:33.040 --> 00:07:34.290
I'll write this in cursive.

00:07:38.860 --> 00:07:40.100
1-tert-butyl.

00:07:40.100 --> 00:07:42.490
Then the next one
alphabetically

00:07:42.490 --> 00:07:43.810
is the heptyl group.

00:07:43.810 --> 00:07:46.680
That's H for heptyl, so
then it is 5-heptyl.

00:07:51.790 --> 00:08:00.520
And then we have the propyl, and
then it is 2-propyl, and

00:08:00.520 --> 00:08:10.120
then finally cyclononane,
and we're done!


Correction - 2-propylheptane should never be the name!

WEBVTT
Kind: captions
Language: en

00:00:00.570 --> 00:00:03.340
In the last video, we tried
to draw a 2-Propylheptane.

00:00:09.900 --> 00:00:13.350
And we did our best attempt at
drawing it, but it was pointed

00:00:13.350 --> 00:00:16.420
out that this wouldn't even be
called a 2-Propylheptane to

00:00:16.420 --> 00:00:16.900
begin with.

00:00:16.900 --> 00:00:19.140
So you actually should never
see something called

00:00:19.140 --> 00:00:20.500
2-Propylheptane.

00:00:20.500 --> 00:00:22.130
Let me show you what
I'm talking about.

00:00:22.130 --> 00:00:23.930
So when do you see something
like this, you might

00:00:23.930 --> 00:00:26.310
immediately say-- and the way
we drew it was actually

00:00:26.310 --> 00:00:29.570
correct, it just wouldn't be
called 2-Propylheptane.

00:00:29.570 --> 00:00:30.950
So you say heptane.

00:00:30.950 --> 00:00:34.600
So that is a seven
carbon alkane.

00:00:34.600 --> 00:00:41.050
No double bond, so one, two,
three, four, five, six, seven.

00:00:41.050 --> 00:00:45.490
And then on the second carbon,
so you have one, two, three,

00:00:45.490 --> 00:00:50.420
four, five, six, seven, we
have a propyl group.

00:00:50.420 --> 00:00:53.140
Propyl, that is three carbons.

00:00:53.140 --> 00:00:56.400
So on the second carbon we
have a propyl group.

00:00:56.400 --> 00:00:57.700
That's three carbons.

00:00:57.700 --> 00:01:01.090
So that is one, two, three.

00:01:01.090 --> 00:01:03.100
And so the way we drew it
was just like this.

00:01:03.100 --> 00:01:06.950
And so if someone gave you
2-Propylheptane, this would be

00:01:06.950 --> 00:01:08.010
what you would draw.

00:01:08.010 --> 00:01:10.380
But you wouldn't call this
2-Propylheptane.

00:01:10.380 --> 00:01:12.750
Because remember, if you're
given the molecule you look

00:01:12.750 --> 00:01:16.020
for the longest chain and the
longest chain here is not the

00:01:16.020 --> 00:01:16.730
heptane chain.

00:01:16.730 --> 00:01:19.880
It is not one, two, three, it is
not this thing in magenta--

00:01:19.880 --> 00:01:21.930
in this kind of mauve color.

00:01:21.930 --> 00:01:24.550
It's this chain where
you start over here.

00:01:24.550 --> 00:01:28.870
If you start over here, one,
two, three, four, five, six,

00:01:28.870 --> 00:01:32.490
seven, eight, nine, you actually
get a longer chain.

00:01:32.490 --> 00:01:36.870
So this would actually be the
backbone of this molecule

00:01:36.870 --> 00:01:38.850
right over there.

00:01:38.850 --> 00:01:41.860
That right over there would be
the backbone, and so you

00:01:41.860 --> 00:01:42.830
would number it.

00:01:42.830 --> 00:01:45.590
You start numbering closest to
the group that's attached, so

00:01:45.590 --> 00:01:52.460
one, two, three, four, five,
six, seven, eight, nine.

00:01:52.460 --> 00:01:55.500
So you have nine carbons in
your backbone, so we're

00:01:55.500 --> 00:01:57.560
dealing with nonane.

00:01:57.560 --> 00:02:00.450
We're dealing with nonane.

00:02:00.450 --> 00:02:04.410
And you have a methyl group:
one carbon attached to the

00:02:04.410 --> 00:02:06.880
fourth carbon of our
main backbone.

00:02:06.880 --> 00:02:13.780
So this is going to be four
methyl, this is our methyl

00:02:13.780 --> 00:02:15.340
group right here,
4-Methylnonane.

00:02:20.710 --> 00:02:25.030
So it was brought up, I think
the user name is Minoctu, and

00:02:25.030 --> 00:02:28.200
they correctly corrected me,
that there would never be such

00:02:28.200 --> 00:02:29.490
a thing as 2-Propylheptane.

00:02:29.490 --> 00:02:30.560
I just made that up.

00:02:30.560 --> 00:02:34.010
If someone were to, kind of,
label this molecule they would

00:02:34.010 --> 00:02:36.665
call it 4-Methylnonane
and ask you draw it.

00:02:36.665 --> 00:02:38.815
But either way, both of
these would point you

00:02:38.815 --> 00:02:40.390
in the right direction.

00:02:40.390 --> 00:02:43.140
This would just be the incorrect
name for it, because

00:02:43.140 --> 00:02:45.370
you'd be looking at-- if someone
gave you this molecule

00:02:45.370 --> 00:02:47.590
and you named it this way,
that would be incorrect.

00:02:47.590 --> 00:02:48.750
So I apologize for this.

00:02:48.750 --> 00:02:51.360
This is 4-Methylnonane.

00:02:51.360 --> 00:02:54.850
If you do heptane you're not
finding the longest chain.


Organic chemistry naming examples 2

WEBVTT
Kind: captions
Language: en

00:00:00.390 --> 00:00:02.190
I've pre-drawn some
molecules here.

00:00:02.190 --> 00:00:06.370
Let's see if we can use what
we know to name them.

00:00:06.370 --> 00:00:06.960
So what do we have?

00:00:06.960 --> 00:00:09.660
This first molecule right here,
I have a bunch of rings.

00:00:09.660 --> 00:00:13.950
This is a one, two, three, four,
five, six carbon ring.

00:00:13.950 --> 00:00:16.700
These are each four carbon
rings: one, two, three, four,

00:00:16.700 --> 00:00:19.790
one, two, three, four, so the
largest ring is essentially

00:00:19.790 --> 00:00:21.530
going to be our backbone.

00:00:21.530 --> 00:00:23.450
It's going to be this six-carbon
ring right here:

00:00:23.450 --> 00:00:28.650
one, two, three, four,
five, six carbons.

00:00:28.650 --> 00:00:35.410
That is a cyclohexane,
all double bonds.

00:00:35.410 --> 00:00:38.000
That's where we get the -ane,
six carbons hex-, it's in a

00:00:38.000 --> 00:00:40.870
cycle, cyclo-, and then
we have two of

00:00:40.870 --> 00:00:42.740
these four-carbon rings.

00:00:42.740 --> 00:00:45.790
So four carbons, we're dealing
with the prefix

00:00:45.790 --> 00:00:48.520
but-, but- for four.

00:00:48.520 --> 00:00:52.155
We've got two of them, so both
of these are butyl groups.

00:00:57.970 --> 00:00:59.070
But they're in a cycle,
so they're

00:00:59.070 --> 00:01:00.810
actually cyclobutyl groups.

00:01:05.220 --> 00:01:07.740
We have two things attached
to this ring right there.

00:01:07.740 --> 00:01:09.440
If we only had one thing
attached to it, you wouldn't

00:01:09.440 --> 00:01:10.120
have to number it.

00:01:10.120 --> 00:01:11.710
But when you have two
things, you start

00:01:11.710 --> 00:01:13.280
numbering at one of them.

00:01:13.280 --> 00:01:15.690
Let's say we start numbering
here, and you go in the

00:01:15.690 --> 00:01:18.200
direction so that the next group
has the lowest number.

00:01:18.200 --> 00:01:19.140
So in this case, you
want to go in the

00:01:19.140 --> 00:01:20.400
counterclockwise direction.

00:01:20.400 --> 00:01:22.340
If we went this way, it
would be one, two,

00:01:22.340 --> 00:01:23.700
three, four, five.

00:01:23.700 --> 00:01:24.530
This guy would be a five.

00:01:24.530 --> 00:01:25.790
If we go in the
counterclockwise, it would be

00:01:25.790 --> 00:01:28.080
one, two, three.

00:01:28.080 --> 00:01:30.160
This guy will only be a three.

00:01:30.160 --> 00:01:33.420
So this right here, we have
two cyclobutyls, so it's

00:01:33.420 --> 00:01:34.670
dicyclobutyl.

00:01:45.540 --> 00:01:48.760
We have two of them and
they are at the

00:01:48.760 --> 00:01:51.520
one and three positions.

00:01:51.520 --> 00:01:54.210
So at the one and three
position, I have two

00:01:54.210 --> 00:02:00.110
cyclobutyls on my cyclohexane
main ring.

00:02:00.110 --> 00:02:01.880
Let's try this one right here.

00:02:01.880 --> 00:02:06.390
I have a five-carbon ring, one,
two, three, four, five

00:02:06.390 --> 00:02:11.330
right there, and then I have a
one, two, three, four, five,

00:02:11.330 --> 00:02:13.930
six-carbon ring right there,
so this is going

00:02:13.930 --> 00:02:15.960
to be the main ring.

00:02:15.960 --> 00:02:17.210
That is a cyclohexane.

00:02:20.690 --> 00:02:24.850
It has six carbons on them in
a cycle, all single bonds.

00:02:24.850 --> 00:02:28.930
Attached to that, I
have a cyclopentyl

00:02:28.930 --> 00:02:31.340
group, -yl for the group.

00:02:31.340 --> 00:02:38.260
This is a cyclopentyl
group on it.

00:02:38.260 --> 00:02:41.270
We don't have to number it
because it's only one group

00:02:41.270 --> 00:02:42.250
attached to the main ring.

00:02:42.250 --> 00:02:44.140
If there was another group, we
would have to number it like

00:02:44.140 --> 00:02:45.310
we did up here.

00:02:45.310 --> 00:02:46.540
This is cyclopentyl.

00:02:46.540 --> 00:02:47.810
That's this part right here.

00:02:47.810 --> 00:02:49.790
Cyclopentyl attached
to cyclohexane:

00:02:49.790 --> 00:02:51.040
cyclopentylcyclohexane.

00:02:53.410 --> 00:02:55.180
Let's try this one over here.

00:02:55.180 --> 00:02:57.630
The first thing we want to do,
there's no cycles here, but we

00:02:57.630 --> 00:03:00.590
have to identify the
longest chain.

00:03:00.590 --> 00:03:02.040
To do that, let's just
count it out.

00:03:02.040 --> 00:03:06.110
It could be one, two, three,
four, five, six, seven.

00:03:06.110 --> 00:03:07.520
That's not the longest chain.

00:03:07.520 --> 00:03:11.430
Maybe it's one, two, three,
four, five, six, seven, eight.

00:03:11.430 --> 00:03:13.510
That looks like the longest
chain, so let's make that the

00:03:13.510 --> 00:03:15.670
longest chain.

00:03:15.670 --> 00:03:18.940
Let's make that the longest
chain right over there.

00:03:22.820 --> 00:03:25.720
We want to start numbering in
the direction so we encounter

00:03:25.720 --> 00:03:27.910
the first attached groups first.
We do want to start

00:03:27.910 --> 00:03:30.900
numbering down here, because we
have groups attached right

00:03:30.900 --> 00:03:31.650
on the two carbon.

00:03:31.650 --> 00:03:33.710
If we started over here, we'd
have to go pretty far until

00:03:33.710 --> 00:03:35.040
something's attached.

00:03:35.040 --> 00:03:40.870
So we go one, two, three,
four, five, six.

00:03:40.870 --> 00:03:41.970
seven.

00:03:41.970 --> 00:03:42.840
eight.

00:03:42.840 --> 00:03:45.910
We know we're dealing with an
octane, all single bonds.

00:03:45.910 --> 00:03:47.190
It's not a cyclooctane.

00:03:47.190 --> 00:03:48.790
It's not in a cycle,
so we know we're

00:03:48.790 --> 00:03:50.040
dealing with an octane.

00:03:53.290 --> 00:03:55.730
Now we just have to add
the groups to it.

00:03:55.730 --> 00:03:58.540
So what do we have here?

00:03:58.540 --> 00:04:00.170
This right here is
just one carbon

00:04:00.170 --> 00:04:01.170
attached to the main chain.

00:04:01.170 --> 00:04:03.780
This is another carbon attached
to the main chain.

00:04:03.780 --> 00:04:07.500
Both of these right here
are methyl groups.

00:04:07.500 --> 00:04:09.410
Meth- is for one carbon.

00:04:09.410 --> 00:04:12.890
Those are methyl groups.

00:04:12.890 --> 00:04:13.730
If you look at all of
them, these are

00:04:13.730 --> 00:04:14.650
the only methyl groups.

00:04:14.650 --> 00:04:16.820
These two up here aren't methyl
groups, so we have two

00:04:16.820 --> 00:04:18.529
methyl groups on our
entire chain, so

00:04:18.529 --> 00:04:21.860
it's going to be dimethyl.

00:04:21.860 --> 00:04:24.940
Both of the methyl groups our
at our two position, so this

00:04:24.940 --> 00:04:27.820
is going to be 2,2-dimethyl.

00:04:27.820 --> 00:04:30.820
This part right here is 2,2.

00:04:30.820 --> 00:04:32.970
That right there is
2,2-dimethyl.

00:04:32.970 --> 00:04:35.390
We're going to decide what order
to write it after we

00:04:35.390 --> 00:04:37.360
figure out what these are called
because it has to be in

00:04:37.360 --> 00:04:38.780
alphabetical order.

00:04:38.780 --> 00:04:40.140
This is 2,2-dimethyl.

00:04:40.140 --> 00:04:41.490
The whole chain is an octane.

00:04:41.490 --> 00:04:44.100
What are these over here?

00:04:44.100 --> 00:04:47.470
How many carbons do
we have here?

00:04:47.470 --> 00:04:48.800
One, two, three.

00:04:48.800 --> 00:04:49.670
They actually look the same.

00:04:49.670 --> 00:04:50.990
We have one, two, three here.

00:04:50.990 --> 00:04:53.070
We have one, two, three
there, so these

00:04:53.070 --> 00:04:54.550
are both propyl groups.

00:04:59.140 --> 00:05:02.600
If we deal with common names,
this is kind of that Y shape.

00:05:02.600 --> 00:05:04.920
You could call it sec-propyl
because this carbon right here

00:05:04.920 --> 00:05:06.480
that's attached to the main
chain is attached

00:05:06.480 --> 00:05:07.820
to two other carbons.

00:05:07.820 --> 00:05:10.730
But the more common one, because
it forms this Y shape,

00:05:10.730 --> 00:05:11.980
is isopropyl.

00:05:14.470 --> 00:05:16.600
We have two isopropyl groups.

00:05:16.600 --> 00:05:17.970
These are both isopropyl.

00:05:24.600 --> 00:05:25.850
We would have diisopropyl.

00:05:35.520 --> 00:05:37.890
They're occurring at the four
and five positions, two

00:05:37.890 --> 00:05:39.370
isopropyls at four and five.

00:05:39.370 --> 00:05:40.620
This is 4,5-diisopropyl.

00:05:43.050 --> 00:05:45.880
That's that group and that
group right there are

00:05:45.880 --> 00:05:47.010
accounted for with this.

00:05:47.010 --> 00:05:49.780
Now we have to just figure out
the order that we write it in.

00:05:49.780 --> 00:05:53.360
You ignore the di- or the tri-
out front and you just look at

00:05:53.360 --> 00:05:54.580
them in alphabetical order.

00:05:54.580 --> 00:05:56.570
We have an I for isopropyl.

00:05:56.570 --> 00:05:59.410
We have an M for methyl.

00:05:59.410 --> 00:06:03.420
Let's write the isopropyl first.
I've actually seen some

00:06:03.420 --> 00:06:07.110
people want to go for the p, but
the main thing I ignore is

00:06:07.110 --> 00:06:08.940
just the di- or the tri- in
front of the isopropyl.

00:06:08.940 --> 00:06:10.950
You shouldn't involve that.

00:06:10.950 --> 00:06:13.110
But everything after that,
you do involve.

00:06:13.110 --> 00:06:18.170
So I'll write the isopropyl
first. I comes before M, so

00:06:18.170 --> 00:06:20.590
this is going to be-- if we were
going to write the whole

00:06:20.590 --> 00:06:32.890
thing, this is going to be
4,5-diisopropyl, 2,2-dimethyl.

00:06:36.240 --> 00:06:37.320
Actually, this should
be a comma here.

00:06:37.320 --> 00:06:38.570
4,5-diisopropyl-
2,2-dimethyloctane.

00:06:52.680 --> 00:06:53.580
And we're done.

00:06:53.580 --> 00:06:54.800
But this was just
the common name.

00:06:54.800 --> 00:06:58.480
You might remember that when we
deal with iso- or sec- or

00:06:58.480 --> 00:07:02.400
tert- butyl or propyl, that's
the common name.

00:07:02.400 --> 00:07:08.840
If we want the systematic name,
we can start at where we

00:07:08.840 --> 00:07:12.730
are attached to the main chain
and view that as one and then

00:07:12.730 --> 00:07:15.230
make the longest chain
with that as one.

00:07:15.230 --> 00:07:17.680
And so you could say that we
have a chain there and this

00:07:17.680 --> 00:07:19.750
would be both of these cases.

00:07:19.750 --> 00:07:21.950
So this is one, two carbons.

00:07:21.950 --> 00:07:23.530
Two carbons, we're dealing
with an ethyl.

00:07:26.270 --> 00:07:30.520
And on the first carbon, you
have a methyl attached to it.

00:07:30.520 --> 00:07:37.230
So you could also call each of
these groups a 1-methylethyl

00:07:37.230 --> 00:07:39.060
instead of an isopropyl.

00:07:39.060 --> 00:07:41.550
So you can either say isopropyl
for each of these

00:07:41.550 --> 00:07:44.470
groups or you could call each
of them a methylethyl if you

00:07:44.470 --> 00:07:45.850
do systematic naming.

00:07:48.600 --> 00:07:51.320
We have two of these
1-methylethyl groups, just

00:07:51.320 --> 00:07:53.560
like we had two isopropyl
groups.

00:07:53.560 --> 00:07:56.780
If you're using common naming,
you can say diisopropyl to say

00:07:56.780 --> 00:07:58.150
you have two of these groups.

00:07:58.150 --> 00:08:00.320
When you're using systematic
naming, you don't say

00:08:00.320 --> 00:08:03.700
di-1-methylethyl, although that
would probably would get

00:08:03.700 --> 00:08:04.650
the point across.

00:08:04.650 --> 00:08:07.590
You use bis-.

00:08:07.590 --> 00:08:11.560
Since we have two of them,
instead of writing di-, you

00:08:11.560 --> 00:08:13.450
write bis-.

00:08:13.450 --> 00:08:17.940
You write bis-(1-methylethyl)
That means you have two of

00:08:17.940 --> 00:08:22.100
these things right there, and
it's still in the four and the

00:08:22.100 --> 00:08:23.710
five position.

00:08:23.710 --> 00:08:26.410
If you look at it in
alphabetical order now,

00:08:26.410 --> 00:08:30.180
methylethyl comes after
methyl, right?

00:08:30.180 --> 00:08:31.610
So the order will now change.

00:08:31.610 --> 00:08:34.799
So now if you want to write it
with systematic naming, it

00:08:34.799 --> 00:08:36.320
would be written as
2,2-dimethyl.

00:08:40.490 --> 00:08:41.950
That's these two guys.

00:08:41.950 --> 00:08:44.710
2,2-dimethylethyl, then you
would write this guy, so the

00:08:44.710 --> 00:08:46.640
order changed for the two
groups just based on how

00:08:46.640 --> 00:08:47.680
they're named.

00:08:47.680 --> 00:08:56.980
Bis-, and then over here you
have two 1-methylethyl groups.

00:08:56.980 --> 00:08:58.810
I know it's confusing, but when
you just break it down,

00:08:58.810 --> 00:09:02.090
it actually makes a reasonable
amount of sense.

00:09:02.090 --> 00:09:04.100
You have two of these
methylethyl groups.

00:09:04.100 --> 00:09:07.170
Oh, sorry, I forgot where
they're located.

00:09:07.170 --> 00:09:11.340
So we have them at the four and
five position, so in the

00:09:11.340 --> 00:09:20.810
four and five position,
we have two, so

00:09:20.810 --> 00:09:27.345
bis-(1methylethyl) groups.

00:09:30.230 --> 00:09:32.220
I know it's a little daunting
now, but it all makes sense

00:09:32.220 --> 00:09:33.470
when you break it down.

00:09:35.760 --> 00:09:39.780
And then we can just add
the octane at the end.

00:09:39.780 --> 00:09:42.590
Let me scroll over to the
right a little bit.

00:09:42.590 --> 00:09:45.430
Octane, and we're done..

00:09:45.430 --> 00:09:47.113
Now this might seem more
confusing, but when you break

00:09:47.113 --> 00:09:47.680
it down, it makes sense.

00:09:47.680 --> 00:09:50.680
We have octane as
the backbone.

00:09:50.680 --> 00:09:52.240
We have two methyls.

00:09:52.240 --> 00:09:54.255
They're both sitting on
the two position.

00:09:54.255 --> 00:09:57.300
So you have two methyls sitting
on the two position,

00:09:57.300 --> 00:10:00.180
and then you have two
1-methylethyl groups sitting

00:10:00.180 --> 00:10:01.560
at the four and five
positions.

00:10:01.560 --> 00:10:05.910
So in the four and five
position, 1-methylethyl.

00:10:05.910 --> 00:10:08.230
You have an ethyl, and in the
one position you have a

00:10:08.230 --> 00:10:10.720
methyl, so that's
all it's saying.

00:10:10.720 --> 00:10:13.870
Or another way to think about
it, just in case this doesn't

00:10:13.870 --> 00:10:16.590
confuse you enough, you could
call it that, or you could say

00:10:16.590 --> 00:10:17.840
4,5-diisopropyl.

00:10:19.590 --> 00:10:21.950
these two things are the same
thing: common naming,

00:10:21.950 --> 00:10:22.670
systematic.

00:10:22.670 --> 00:10:25.160
Hopefully, you found
that useful.


More Organic Chemistry Naming Examples 1

WEBVTT
Kind: captions
Language: en

00:00:00.000 --> 00:00:03.270
I think we're ready now to
tackle some more or even more

00:00:03.270 --> 00:00:04.550
complicated examples.

00:00:04.550 --> 00:00:06.650
So let's draw something
crazy here.

00:00:06.650 --> 00:00:10.200
So let's see, let
me draw a chain.

00:00:10.200 --> 00:00:14.990
Let me draw it like that.

00:00:14.990 --> 00:00:17.680
And so like we've done in all
of the examples, you want to

00:00:17.680 --> 00:00:18.890
find the longest chain.

00:00:18.890 --> 00:00:19.730
We could count from here.

00:00:19.730 --> 00:00:23.390
One, two, three, four, five,
six, seven, eight, or maybe

00:00:23.390 --> 00:00:26.350
it's one, two, three, four,
five, six, seven.

00:00:26.350 --> 00:00:26.690
No.

00:00:26.690 --> 00:00:30.220
Or maybe it's one, two, three,
four, five, six, seven,

00:00:30.220 --> 00:00:32.150
eight, nine, ten.

00:00:32.150 --> 00:00:34.840
That is our longest chain.

00:00:34.840 --> 00:00:36.940
Let me make that in green.

00:00:36.940 --> 00:00:41.480
So our longest chain
here is in green.

00:00:41.480 --> 00:00:44.910
So this decane-- sorry,
this backbone has

00:00:44.910 --> 00:00:46.380
ten carbons in it.

00:00:46.380 --> 00:00:48.590
The prefix for ten is dec-.

00:00:48.590 --> 00:00:52.750
It is an alkane since it has
all single bonds, so we can

00:00:52.750 --> 00:00:55.240
write decane for the backbone.

00:00:55.240 --> 00:01:02.210
And then it has a group right
here and this group consists

00:01:02.210 --> 00:01:06.540
of one, two carbons attached
to the backbone.

00:01:06.540 --> 00:01:09.640
The prefix for two carbons
is eth-, so

00:01:09.640 --> 00:01:11.420
this is an ethyl group.

00:01:11.420 --> 00:01:14.820
The -yl is because it's a group
attached to the main

00:01:14.820 --> 00:01:17.510
alkane chain, so we call
this ethyldecane.

00:01:20.160 --> 00:01:22.640
But we have to specify where the
ethyl group is attached.

00:01:22.640 --> 00:01:25.090
And we want to give it as low of
a number as possible, so we

00:01:25.090 --> 00:01:28.160
start counting on the
side closest to it.

00:01:28.160 --> 00:01:33.530
So it's one, two, three,
four, five, so this is

00:01:33.530 --> 00:01:36.130
5-ethyldecane.

00:01:36.130 --> 00:01:39.210
Now let's complicate this
a little bit more.

00:01:39.210 --> 00:01:41.410
So let me just to copy
and paste this.

00:01:46.410 --> 00:01:48.260
So I have pasted it there.

00:01:48.260 --> 00:01:50.810
And let me complicate this
molecule a little bit more.

00:01:50.810 --> 00:01:52.635
Let me add another ethyl
group to it.

00:01:55.440 --> 00:02:00.200
So let's say we have another
ethyl group over there.

00:02:00.200 --> 00:02:01.560
Now, what is this going to be?

00:02:01.560 --> 00:02:04.370
Well, the longest chain is still
going to be that thing

00:02:04.370 --> 00:02:06.840
in green, so it's still
going to be a decane.

00:02:10.009 --> 00:02:12.350
But now we have two ethyl
groups, one on the five

00:02:12.350 --> 00:02:14.990
carbon, one, two, three,
four, five, and then

00:02:14.990 --> 00:02:16.335
one on the six carbon.

00:02:18.950 --> 00:02:21.510
So we write here-- you might
be tempted to write

00:02:21.510 --> 00:02:25.460
5-ethyl-6-ethyldecane, which
really wouldn't be wrong, but

00:02:25.460 --> 00:02:27.220
it would just be maybe
more letters

00:02:27.220 --> 00:02:28.180
than you want to write.

00:02:28.180 --> 00:02:30.820
Instead you write
5,6-diethyldecane.

00:02:41.380 --> 00:02:44.950
The 5,6- tells us the two
carbons on the main backbone

00:02:44.950 --> 00:02:47.960
that the ethyl groups are
attached to, and the di- says

00:02:47.960 --> 00:02:49.670
that we have two ethanes.

00:02:49.670 --> 00:02:51.950
Or two ethyl groups, I should
say, not ethane groups.

00:02:51.950 --> 00:02:56.250
Two ethyl groups, one over here
and one right over here.

00:02:56.250 --> 00:03:01.010
Now, let's make it even
more complex.

00:03:01.010 --> 00:03:04.380
Let's take our thing and let's
make it even more complex.

00:03:04.380 --> 00:03:12.280
So let's copy it and let
us paste it, edit,

00:03:12.280 --> 00:03:17.376
paste, just like that.

00:03:17.376 --> 00:03:18.280
Let's paste it.

00:03:18.280 --> 00:03:20.880
Let me make it a little
bit lower over here.

00:03:20.880 --> 00:03:23.170
So the exact same thing we just
dealt with, but let's add

00:03:23.170 --> 00:03:26.810
one more group to it.

00:03:26.810 --> 00:03:30.080
Let's say it looks something
like this.

00:03:30.080 --> 00:03:32.610
Let's say on that five carbon--
let's say on that six

00:03:32.610 --> 00:03:36.620
carbon right there, I have
a group that looks

00:03:36.620 --> 00:03:37.560
something like this.

00:03:37.560 --> 00:03:39.300
What is this is going
to be called?

00:03:39.300 --> 00:03:41.040
And here we probably want to
break it down a little bit.

00:03:41.040 --> 00:03:43.080
We still have the backbone,
so it's still

00:03:43.080 --> 00:03:44.330
going to be a decane.

00:03:48.790 --> 00:03:50.530
But let's just do
it step by step.

00:03:50.530 --> 00:03:53.500
So we know that this right here,
this is an ethyl group.

00:03:53.500 --> 00:03:57.410
It's on the five carbon,
so that is a 5-ethyl.

00:03:57.410 --> 00:03:59.340
This is another ethyl group
on the six carbon,

00:03:59.340 --> 00:04:02.440
so that is a 6-ethyl.

00:04:02.440 --> 00:04:03.980
Now, we have this
group over here.

00:04:03.980 --> 00:04:06.030
So how many carbons
are on this group?

00:04:06.030 --> 00:04:09.470
Well, we have one, two,
three carbons on it.

00:04:09.470 --> 00:04:12.400
We have three carbons on it, so
we might want to just call

00:04:12.400 --> 00:04:14.840
it a propyl group, but
notice something.

00:04:14.840 --> 00:04:16.959
We are attached to the carbon,
and then it later

00:04:16.959 --> 00:04:17.930
branches off into two.

00:04:17.930 --> 00:04:19.940
It actually immediately
branches off into two.

00:04:19.940 --> 00:04:24.330
So we could actually call this
either sec-propyl, so this

00:04:24.330 --> 00:04:31.730
right here, we can either call
it sec-propyl, or because it

00:04:31.730 --> 00:04:34.270
is connected away from the-- I
guess it's connected directly

00:04:34.270 --> 00:04:37.060
to the branch the way a
propyl group works.

00:04:37.060 --> 00:04:38.910
You could connect it and it
immediately branches, because

00:04:38.910 --> 00:04:40.180
you only have three carbons.

00:04:40.180 --> 00:04:44.490
So just to clarify things,
it's sec- because we're

00:04:44.490 --> 00:04:46.670
attached to two carbons
right there.

00:04:46.670 --> 00:04:48.880
But sec-propyl isn't what
people normally call it.

00:04:48.880 --> 00:04:50.130
They normally call
it isopropyl.

00:04:53.760 --> 00:04:56.820
And the iso- root comes from
anything of the form.

00:04:56.820 --> 00:05:01.110
So if I have a group that looks
like this, this would be

00:05:01.110 --> 00:05:06.360
isobutyl, because we have one,
two, three, four carbons, and

00:05:06.360 --> 00:05:09.130
we are attached right here, so
this is where we would attach

00:05:09.130 --> 00:05:10.030
to the main backbone.

00:05:10.030 --> 00:05:16.670
If I have a group that
looks like this,

00:05:16.670 --> 00:05:18.990
this would be isopentyl.

00:05:18.990 --> 00:05:21.700
I have one, two, three,
four, five carbons.

00:05:21.700 --> 00:05:23.590
I'm attached away
from the branch.

00:05:23.590 --> 00:05:27.190
But if we go one step closer,
so we're attached just like

00:05:27.190 --> 00:05:28.550
this, we're attached
to the original

00:05:28.550 --> 00:05:31.720
group, this is isopropyl.

00:05:31.720 --> 00:05:33.170
One, two, three carbons.

00:05:33.170 --> 00:05:37.570
Let me write-- isopropyl,
isobutyl, isopentyl.

00:05:37.570 --> 00:05:40.900
Notice what the isos-- the isos
are like Y's, I guess is

00:05:40.900 --> 00:05:42.330
the best way of thinking of it,
and you're attached to the

00:05:42.330 --> 00:05:43.150
base of the Y.

00:05:43.150 --> 00:05:45.220
In this case, you're almost
attached to the base of a V,

00:05:45.220 --> 00:05:46.630
but, hopefully, you
get the idea.

00:05:46.630 --> 00:05:50.710
So the common name for this
group would be isopropyl, or

00:05:50.710 --> 00:05:53.500
if we wanted to use the
systematic naming, we could

00:05:53.500 --> 00:05:57.720
just start at one as being-- let
me do this in a good color

00:05:57.720 --> 00:06:00.490
--as the carbon we are attached
to, and then we only

00:06:00.490 --> 00:06:02.670
have two carbons right
over there.

00:06:02.670 --> 00:06:04.260
So if we have two carbons,
we're dealing

00:06:04.260 --> 00:06:05.510
with an ethyl group.

00:06:08.130 --> 00:06:11.430
And then you could say that
you have a methyl group

00:06:11.430 --> 00:06:14.165
attached to the first carbon, so
it would be 1-methylethyl.

00:06:19.850 --> 00:06:23.210
So this could either be called
an isopropyl group, or a

00:06:23.210 --> 00:06:25.520
1-methylethyl group.

00:06:25.520 --> 00:06:28.300
And in either case-- let me
put that in parentheses.

00:06:28.300 --> 00:06:30.503
In either case, it's attached
to the six carbon.

00:06:34.360 --> 00:06:36.750
So the prefixes are going to
be on the six carbon on our

00:06:36.750 --> 00:06:44.970
main-- we have a 1-methylethyl,
where the

00:06:44.970 --> 00:06:47.430
methyl is attached to the first
carbon on the ethyl

00:06:47.430 --> 00:06:53.710
chain, or we could call this a
6-isopropyl group attached to

00:06:53.710 --> 00:06:55.370
the six carbon.

00:06:55.370 --> 00:06:58.500
Now, when we decide how to write
it, how do we know--

00:06:58.500 --> 00:06:59.720
we're going to have to
write essentially the

00:06:59.720 --> 00:07:02.200
ethyl and the isopropyl.

00:07:02.200 --> 00:07:04.100
We're going to have to
write all of that in

00:07:04.100 --> 00:07:05.830
front of the decane.

00:07:05.830 --> 00:07:07.920
How do we decide whether
to write the eth-

00:07:07.920 --> 00:07:09.030
or the propyl- first?

00:07:09.030 --> 00:07:11.010
Well, here you just do it
in alphabetical order.

00:07:11.010 --> 00:07:12.220
And actually these
little prefixes

00:07:12.220 --> 00:07:13.960
in front don't matter.

00:07:13.960 --> 00:07:15.800
So you compare the P to the E.

00:07:15.800 --> 00:07:19.130
Eth-, E comes first in
alphabetical order, so this

00:07:19.130 --> 00:07:22.155
would be 5,6-diethyl.

00:07:26.790 --> 00:07:30.640
So even though D-- well, D comes
even before E, but you

00:07:30.640 --> 00:07:31.970
don't even count that prefix.

00:07:31.970 --> 00:07:33.730
The E is what matters.

00:07:33.730 --> 00:07:38.610
Diethyl, and then
we could say,

00:07:38.610 --> 00:07:39.860
diethyl-6-isopropyldecane.

00:07:48.290 --> 00:07:50.140
This is the common name:
6-isopropyldecane.

00:07:57.340 --> 00:07:59.150
This would be the common
name for it.

00:07:59.150 --> 00:08:01.000
If we want to use the systematic
name, we would

00:08:01.000 --> 00:08:04.970
replace the 6-isopropyl
with 6,1-methylethyl.

00:08:04.970 --> 00:08:06.170
So let me write that down.

00:08:06.170 --> 00:08:09.250
So let me just copy this part.

00:08:09.250 --> 00:08:13.870
So copy and paste right there.

00:08:13.870 --> 00:08:17.500
And then I can copy and
paste this right here.

00:08:17.500 --> 00:08:20.340
Copy and paste.

00:08:20.340 --> 00:08:21.590
So it becomes
5,6-diethyl-6-1-methylethyl.

00:08:24.430 --> 00:08:26.120
I know it's very confusing when
you see it, but when you

00:08:26.120 --> 00:08:27.780
break it down, you really
could-- you would be able to

00:08:27.780 --> 00:08:29.220
draw this from the structure.

00:08:29.220 --> 00:08:38.320
And then finally you finish
with a decane.

00:08:38.320 --> 00:08:40.940
So hopefully, these examples
don't confuse you too much.

00:08:40.940 --> 00:08:43.400
In the next few videos, we'll
do more and more examples.

00:08:43.400 --> 00:08:46.050
Because I think with the
nomenclature on the organic

00:08:46.050 --> 00:08:47.960
chemistry, the more examples
you see, the better.

00:08:47.960 --> 00:08:50.260
This is really core, so in the
future you don't get confused

00:08:50.260 --> 00:08:52.130
when people throw out
something like,

00:08:52.130 --> 00:08:53.380
5,6-diethyl-6-(1
-methylethyl)decane.


Common and systematic naming: iso-, sec-, and tert- prefixes

WEBVTT
Kind: captions
Language: en

00:00:00.650 --> 00:00:03.590
Let's see if we can get the
molecular structure for

00:00:03.590 --> 00:00:04.840
butylcyclopentane.

00:00:11.050 --> 00:00:13.980
So you just break this up the
way we've done it in the last

00:00:13.980 --> 00:00:18.970
several videos, the suffix is
-ane, so it is an alkane, all

00:00:18.970 --> 00:00:20.430
single bonds.

00:00:20.430 --> 00:00:25.010
So single bonds.

00:00:25.010 --> 00:00:29.930
It's pentane, so we're dealing
with five carbons on the base,

00:00:29.930 --> 00:00:31.422
or on the backbone.

00:00:31.422 --> 00:00:35.360
So this is five carbons and it's
a cyclopentane, so it's

00:00:35.360 --> 00:00:37.560
five carbons in a ring.

00:00:37.560 --> 00:00:42.360
So its five-carbon ring is the
backbone, and then we have a

00:00:42.360 --> 00:00:45.180
butyl group added to that
five-carbon ring.

00:00:45.180 --> 00:00:46.630
Now, you might say, hey, Sal,
how do I know which

00:00:46.630 --> 00:00:47.940
carbon to add it to?

00:00:47.940 --> 00:00:50.330
When you're dealing with a ring
and you only have one

00:00:50.330 --> 00:00:52.590
group on the ring, it
doesn't matter.

00:00:52.590 --> 00:00:53.640
Let me just show you
what I mean.

00:00:53.640 --> 00:00:55.140
So let's draw the five-carbon
ring.

00:00:55.140 --> 00:00:57.280
Let's draw the cyclopentane.

00:00:57.280 --> 00:01:02.630
So it'll just be a pentagon,
so one, two, three, four,

00:01:02.630 --> 00:01:04.900
five, and it's a ring, so
you can connect them.

00:01:04.900 --> 00:01:07.120
One, two, three, four, five.

00:01:07.120 --> 00:01:09.580
Now, it doesn't matter where
I draw the butyl group.

00:01:09.580 --> 00:01:11.060
It's all symmetric
around there.

00:01:11.060 --> 00:01:13.710
We just have a ring and it's
connected to a butyl group at

00:01:13.710 --> 00:01:14.200
some point.

00:01:14.200 --> 00:01:16.410
It'll start to matter once we
add more than one group.

00:01:16.410 --> 00:01:18.660
So we can just pick any of
these carbons to add

00:01:18.660 --> 00:01:19.890
the butyl group to.

00:01:19.890 --> 00:01:24.450
Now, just as a review, the but-
prefix, that refers to,

00:01:24.450 --> 00:01:28.520
remember, methyl, ethyl,
propyl, or meth-,

00:01:28.520 --> 00:01:29.970
eth-, prop-, but-.

00:01:29.970 --> 00:01:31.800
This is four carbons.

00:01:31.800 --> 00:01:35.780
This is a four-carbon
alkyl group.

00:01:35.780 --> 00:01:37.110
So let me just add it here.

00:01:37.110 --> 00:01:39.760
I could have added it to any of
these carbons around this

00:01:39.760 --> 00:01:40.870
cyclopentane ring.

00:01:40.870 --> 00:01:42.960
So if I just add it right here,
so I'm going to have

00:01:42.960 --> 00:01:43.810
four carbons.

00:01:43.810 --> 00:01:48.170
So one, two, three, four.

00:01:48.170 --> 00:01:51.290
That is the butyl part
of this whole thing.

00:01:51.290 --> 00:01:53.120
And then let me just
attach them up.

00:01:53.120 --> 00:01:56.170
So you might be tempted to just
draw this right there.

00:01:56.170 --> 00:01:57.640
And actually, this
would be right.

00:01:57.640 --> 00:02:00.500
This is butylcyclopentane.

00:02:00.500 --> 00:02:02.390
But a question might arise.

00:02:02.390 --> 00:02:07.030
I just happened to connect the
cyclopentane to the butyl at

00:02:07.030 --> 00:02:09.150
this first carbon on the
butyl right there.

00:02:09.150 --> 00:02:11.080
I could have just as easily
done it like this.

00:02:16.300 --> 00:02:21.570
I could have just as easily had
it like this, where-- let

00:02:21.570 --> 00:02:27.540
me draw my butyl again, so I
have one, two, three, four.

00:02:27.540 --> 00:02:30.370
So, once again, this is a butyl,
but instead of being

00:02:30.370 --> 00:02:34.380
bonded to the cyclopentane on
my first carbon, maybe it's

00:02:34.380 --> 00:02:37.490
bonded right here.

00:02:37.490 --> 00:02:39.570
Let me do it with that
yellow color.

00:02:39.570 --> 00:02:42.240
Maybe it's bonded right here.

00:02:42.240 --> 00:02:45.150
This seems like maybe
this could also be

00:02:45.150 --> 00:02:47.630
butylcyclopentane.

00:02:47.630 --> 00:02:49.440
It looks like we have
a butyl group.

00:02:49.440 --> 00:02:50.700
This is a butyl right here.

00:02:50.700 --> 00:02:54.840
I drew a butyl group right over
here, and I also drew a

00:02:54.840 --> 00:02:56.260
butyl group right over here.

00:02:56.260 --> 00:02:59.470
But these are fundamentally
two different molecular

00:02:59.470 --> 00:03:00.000
structures.

00:03:00.000 --> 00:03:01.430
I'm touching the first
carbon here.

00:03:01.430 --> 00:03:03.850
I'm touching the second
carbon over here.

00:03:03.850 --> 00:03:06.770
Now, there's two ways to
differentiate this.

00:03:06.770 --> 00:03:10.760
One is the common naming and one
is the systematic naming.

00:03:10.760 --> 00:03:12.650
So let me differentiate
between the two.

00:03:12.650 --> 00:03:15.860
So in the common naming, and
this can get a little bit

00:03:15.860 --> 00:03:19.930
involved, and this frankly is
probably the most complicated

00:03:19.930 --> 00:03:22.020
part of naming organic
compounds.

00:03:22.020 --> 00:03:25.540
Systematic is often more
complicated, but it's easier

00:03:25.540 --> 00:03:27.720
to systematically
come up with it.

00:03:27.720 --> 00:03:30.075
So there's a common and then
there's a systematic.

00:03:35.010 --> 00:03:38.440
So the common way of doing
it is, if you just say

00:03:38.440 --> 00:03:42.020
butylcyclopentane, that implies
that you are bonding

00:03:42.020 --> 00:03:44.230
to the first or, depending on
how you view it, the last

00:03:44.230 --> 00:03:45.070
carbon in the chain.

00:03:45.070 --> 00:03:47.940
So this right here is
butylcyclopentane.

00:03:47.940 --> 00:03:51.170
This right here is not just
butylcyclopentane.

00:03:51.170 --> 00:03:54.110
What you would do is you
definitely have a cyclopentane

00:03:54.110 --> 00:03:56.360
ring, so this would definitely
be a cyclopentane.

00:03:58.860 --> 00:04:01.620
Let me put some space here.

00:04:01.620 --> 00:04:03.320
This is definitely going
to be a cyclopentane.

00:04:06.970 --> 00:04:11.690
And you do have a butyl group
on it, so we do have a butyl

00:04:11.690 --> 00:04:17.880
group, but because we are
bonded-- we aren't bonded to

00:04:17.880 --> 00:04:18.490
the first carbon.

00:04:18.490 --> 00:04:20.529
We're bonded to a carbon
that is bonded

00:04:20.529 --> 00:04:21.829
to two other carbons.

00:04:21.829 --> 00:04:22.810
We call this

00:04:22.810 --> 00:04:29.550
sec-butylcyclopentane, so this is sec-.

00:04:29.550 --> 00:04:31.960
And everything I'm doing
is obviously free-hand.

00:04:31.960 --> 00:04:34.120
If you were to see this in
a book, the sec- would be

00:04:34.120 --> 00:04:38.370
italicized, or sometimes
it would be written as

00:04:38.370 --> 00:04:39.620
s-butylcyclopentane.

00:04:48.770 --> 00:04:51.970
And this sec- means that we have
attached to a carbon that

00:04:51.970 --> 00:04:53.440
is touching two other carbons.

00:04:53.440 --> 00:04:55.090
So you look at the butyl group,
and say, well, which of

00:04:55.090 --> 00:04:56.270
these carbons is attached
to two others?

00:04:56.270 --> 00:04:57.740
It's either that one
or that one.

00:04:57.740 --> 00:04:59.830
And regardless of whether you're
attached to this or

00:04:59.830 --> 00:05:02.680
this, if you think about it,
it's fundamentally the same

00:05:02.680 --> 00:05:04.050
molecular structure.

00:05:04.050 --> 00:05:06.920
So that's what you do when
you're attached to that guy

00:05:06.920 --> 00:05:07.460
right over there.

00:05:07.460 --> 00:05:09.400
But what about the situation
where we're dealing with just

00:05:09.400 --> 00:05:10.840
the common names right here?

00:05:10.840 --> 00:05:13.960
What about the situation where
it looks like this?

00:05:13.960 --> 00:05:18.430
So we have our cyclopentane
right there, and we have a-- I

00:05:18.430 --> 00:05:19.960
guess we could call
it a butyl group.

00:05:19.960 --> 00:05:23.040
It'll have four carbons in it,
but let's say that the four

00:05:23.040 --> 00:05:25.780
carbons look something
like this.

00:05:25.780 --> 00:05:30.190
Let's say there are four
carbons, so we have one, two,

00:05:30.190 --> 00:05:36.040
three, four carbons and
we're bonded to this

00:05:36.040 --> 00:05:37.930
one right over here.

00:05:37.930 --> 00:05:42.260
So whenever you're bonded to
one end of the four-carbon

00:05:42.260 --> 00:05:46.860
group and it branches off at the
other end, and it seems a

00:05:46.860 --> 00:05:50.660
little complicated, this only
deals for alkyl groups below

00:05:50.660 --> 00:05:55.290
five or six carbons, this we
call an isobutyl group.

00:05:55.290 --> 00:05:56.370
So let me write this down.

00:05:56.370 --> 00:06:02.920
So this right here, is
sec-butyl, or s-butyl

00:06:02.920 --> 00:06:04.100
sometimes for short.

00:06:04.100 --> 00:06:08.750
This right here, this right
there is iso-butyl.

00:06:11.680 --> 00:06:17.030
It's actually-- iso- that
is an iso-butyl group.

00:06:17.030 --> 00:06:18.710
And then the last thing to
worry about when you're

00:06:18.710 --> 00:06:21.020
dealing with butyl groups
is something like this.

00:06:24.960 --> 00:06:26.350
Let me draw it.

00:06:26.350 --> 00:06:28.160
So you could also draw four
carbons like this.

00:06:28.160 --> 00:06:30.910
You have one carbon,
two, three, four.

00:06:30.910 --> 00:06:34.200
One, two, three, four carbons
and you're attached over here.

00:06:34.200 --> 00:06:38.160
Now this naming, this group
right here-- and you're going

00:06:38.160 --> 00:06:39.800
see the systematic
naming is much

00:06:39.800 --> 00:06:41.480
easier for these compounds.

00:06:41.480 --> 00:06:44.350
This group right here, over
here the carbon you're

00:06:44.350 --> 00:06:45.920
attached to is attached
to two other

00:06:45.920 --> 00:06:49.410
carbons, so it is sec-butyl.

00:06:49.410 --> 00:06:52.820
When you're attached to three
carbons, it is t-butyl, or

00:06:52.820 --> 00:07:00.390
tert-butyl, so this right here
is a tert-butyl group, or

00:07:00.390 --> 00:07:02.170
sometimes called a t-butyl.

00:07:02.170 --> 00:07:03.630
And I really want you
to understand

00:07:03.630 --> 00:07:04.200
the difference here.

00:07:04.200 --> 00:07:07.000
The common naming, it's easier
to say and easier to spell,

00:07:07.000 --> 00:07:08.560
but it's sometimes a
little confusing.

00:07:08.560 --> 00:07:11.390
This is just straight up butyl
so you would call this

00:07:11.390 --> 00:07:13.380
butylcyclopentane.

00:07:13.380 --> 00:07:16.110
This is sec-butyl, because
you have this guy

00:07:16.110 --> 00:07:17.670
connected to two carbons.

00:07:17.670 --> 00:07:21.210
That's where the sec-
comes from.

00:07:21.210 --> 00:07:22.290
Sometimes it'll be s-butyl.

00:07:22.290 --> 00:07:27.570
So this could be called
sec-butylcyclopentane or

00:07:27.570 --> 00:07:29.500
s-butylcyclopentane.

00:07:29.500 --> 00:07:32.660
This, because we're attached
to the end away from this

00:07:32.660 --> 00:07:35.240
branching off, is still a butyl
group, since we have

00:07:35.240 --> 00:07:36.670
four carbons.

00:07:36.670 --> 00:07:39.650
But since we're attached here,
this is iso-butyl, so this is

00:07:39.650 --> 00:07:41.770
iso-butylcyclopentane,

00:07:41.770 --> 00:07:44.350
And then finally, since the
carbon we're attaching to is

00:07:44.350 --> 00:07:48.730
attached to one, two, three
other carbons, it is a

00:07:48.730 --> 00:07:50.750
tert-butyl or a t-butyl group.

00:07:50.750 --> 00:07:54.070
So this is t-butylcyclopentane.

00:07:54.070 --> 00:07:55.630
That's the common naming.

00:07:55.630 --> 00:07:57.890
So maybe I should clear out
systematic here just so it's

00:07:57.890 --> 00:08:01.410
clear to you that everything
we've done

00:08:01.410 --> 00:08:04.820
here is common naming.

00:08:04.820 --> 00:08:05.675
So let me write it down.

00:08:05.675 --> 00:08:08.670
It won't hurt to write them down
again because the more

00:08:08.670 --> 00:08:10.490
familiar you are with
these, the better.

00:08:10.490 --> 00:08:11.740
So this is just
butylcyclopentane.

00:08:18.970 --> 00:08:20.410
This is s- or sec-
butylcyclopentane.

00:08:26.620 --> 00:08:28.330
And this is
iso-butylcyclopentane.

00:08:37.440 --> 00:08:38.990
I'm going off the screen here.

00:08:38.990 --> 00:08:41.230
And then finally, this
is tert-butyl, or

00:08:41.230 --> 00:08:42.480
t-butylcyclopentane.

00:08:45.680 --> 00:08:48.100
Now, I said these are
the common naming.

00:08:48.100 --> 00:08:50.900
What are the systematic
naming?

00:08:50.900 --> 00:08:54.080
Well, in the systematic, this
is still butylcyclopentane.

00:08:54.080 --> 00:08:55.240
So let me write this down.

00:08:55.240 --> 00:09:01.110
Systematic, this is still

00:09:01.110 --> 00:09:02.940
butylcyclopentane, which makes sense.

00:09:02.940 --> 00:09:05.850
This is very clearly
a cyclopentane.

00:09:05.850 --> 00:09:08.040
This is very clearly
a butyl group.

00:09:08.040 --> 00:09:11.120
But in the systematic naming,
what we try to do is we try to

00:09:11.120 --> 00:09:16.900
name this group right here
just as we would name a

00:09:16.900 --> 00:09:19.600
traditional chain, but we
ended it with an -yl.

00:09:19.600 --> 00:09:22.760
So if you look at this right
here, what we do is we just

00:09:22.760 --> 00:09:26.180
consider the chain
where we attach.

00:09:26.180 --> 00:09:30.730
We attached over here, so the
longest chain from that point

00:09:30.730 --> 00:09:33.600
is there and there.

00:09:33.600 --> 00:09:35.540
So if you look at it like that,
it looks like you have

00:09:35.540 --> 00:09:39.550
one, two, three carbons, and you
have one carbon attached

00:09:39.550 --> 00:09:40.220
on the beginning.

00:09:40.220 --> 00:09:43.870
So this little group right here
in the systematic naming,

00:09:43.870 --> 00:09:45.890
this looks like a
one, two, three.

00:09:45.890 --> 00:09:49.520
Three carbons, that's the prop-
prefix, so we're dealing

00:09:49.520 --> 00:09:52.910
with a prop-, and it's all going
to be one group, so it's

00:09:52.910 --> 00:09:54.840
a propyl group.

00:09:54.840 --> 00:09:59.330
This is a propyl group, but it
has a methyl-- remember, meth-

00:09:59.330 --> 00:10:00.500
is one carbon.

00:10:00.500 --> 00:10:03.870
It has a methyl group attached
on the first carbon.

00:10:03.870 --> 00:10:05.435
So this is 1-methylpropyl.

00:10:11.500 --> 00:10:15.130
Now, that describes
just the group.

00:10:15.130 --> 00:10:18.970
1-methylpropyl describes just
this part right here.

00:10:18.970 --> 00:10:21.870
That describes just that
right over there.

00:10:21.870 --> 00:10:25.120
And then to have the whole
compound, to describe the

00:10:25.120 --> 00:10:27.550
whole compound, you put this in
parentheses, so this is the

00:10:27.550 --> 00:10:29.180
systematic naming.

00:10:29.180 --> 00:10:33.040
So 1-methyl-- I put
an L there.

00:10:33.040 --> 00:10:34.490
Let me do it in the
same color.

00:10:34.490 --> 00:10:38.550
1-methyl, because
you're starting

00:10:38.550 --> 00:10:39.850
where you're attaching.

00:10:39.850 --> 00:10:43.810
So 1-methyl, you have a methyl
group right there on that

00:10:43.810 --> 00:10:44.420
first carbon.

00:10:44.420 --> 00:10:45.600
It's a propyl chain.

00:10:45.600 --> 00:10:48.800
One, two, three, propyl,
and then you would say

00:10:48.800 --> 00:10:50.050
cyclopentane.

00:10:54.130 --> 00:10:56.540
That's the systematic
name for that.

00:10:56.540 --> 00:10:59.200
Now if you look at this one
right here, and the common

00:10:59.200 --> 00:11:01.650
name is iso-butyl, what
you do is you

00:11:01.650 --> 00:11:03.520
look at where we attach.

00:11:03.520 --> 00:11:07.110
Where we attached is one,
two, three carbons.

00:11:07.110 --> 00:11:11.940
So once again, I'm doing that
same one, two, three carbons.

00:11:11.940 --> 00:11:15.260
So once again, this
is a propyl.

00:11:15.260 --> 00:11:19.210
Prop- is for three, but with a
methyl group now is attached

00:11:19.210 --> 00:11:23.370
to the one, two, the
second carbon.

00:11:23.370 --> 00:11:26.330
So this is 2-methyl.

00:11:26.330 --> 00:11:28.460
Let me make some space here.

00:11:28.460 --> 00:11:29.710
This is 2-methyl.

00:11:31.960 --> 00:11:34.500
So that describes this
group right here.

00:11:34.500 --> 00:11:36.640
That describes this entire
group cyclopentane.

00:11:39.600 --> 00:11:41.490
Remember, this is a
systematic name.

00:11:41.490 --> 00:11:43.230
You might sometimes see
this referred to as

00:11:43.230 --> 00:11:47.430
iso-butylcyclopentane or
2-methylpropylcyclopentane.

00:11:47.430 --> 00:11:48.890
And this is actually a -yl.

00:11:48.890 --> 00:11:50.530
I spelled it wrong.

00:11:50.530 --> 00:11:53.690
And then finally, we do the same
exact idea here, but it

00:11:53.690 --> 00:11:55.510
becomes a little bit
more interesting.

00:11:55.510 --> 00:11:59.520
Over here, we are attached to
this carbon and the longest

00:11:59.520 --> 00:12:03.190
chain I can do starting with
that carbon is just one chain

00:12:03.190 --> 00:12:04.730
right there.

00:12:04.730 --> 00:12:06.640
So we just have a two-carbon
chain, right?

00:12:06.640 --> 00:12:07.630
One, two.

00:12:07.630 --> 00:12:11.360
The prefix for a two carbon
is ethyl, or eth-.

00:12:11.360 --> 00:12:14.640
Eth-, and since it's
a group, ethyl.

00:12:14.640 --> 00:12:22.970
And then we have two methyl
groups attached right over

00:12:22.970 --> 00:12:25.750
there, and it's attached on
the one carbon, right?

00:12:25.750 --> 00:12:27.180
This is one and this is two.

00:12:27.180 --> 00:12:29.560
We call the one carbon
where we are attached

00:12:29.560 --> 00:12:30.910
to the broader chain.

00:12:30.910 --> 00:12:34.080
So what this is going to be, you
would actually write one

00:12:34.080 --> 00:12:36.960
comma one to show that we have
two groups attached to the

00:12:36.960 --> 00:12:40.050
first carbon and both
of them are methyl.

00:12:40.050 --> 00:12:44.975
So we write 1,1-dimethyl,
di- for two, dimethyl.

00:12:48.120 --> 00:12:50.680
So this entire group right here,
which we also called

00:12:50.680 --> 00:12:53.990
t-butyl, in systematic
naming is 1,1-.

00:12:53.990 --> 00:12:56.020
We have two groups attached
to this first carbon.

00:12:56.020 --> 00:12:57.270
1,1-dimethylethyl.

00:12:58.780 --> 00:12:59.720
That's this whole thing.

00:12:59.720 --> 00:13:02.580
This is the ethyl, and then we
have two methyls attached

00:13:02.580 --> 00:13:03.930
there. that's why
we write 1,1-.

00:13:03.930 --> 00:13:04.940
They're both attached
to the one.

00:13:04.940 --> 00:13:06.320
We have two of them.

00:13:06.320 --> 00:13:08.290
That's why we wrote
di- over there.

00:13:08.290 --> 00:13:12.135
So it's 1,1-dimethylethyl- and
then finally, cyclopentane.

00:13:15.070 --> 00:13:16.750
So hopefully, that doesn't
confuse you too much.

00:13:16.750 --> 00:13:18.640
I think if you watch the video
over and over and try to

00:13:18.640 --> 00:13:20.900
practice it with your own
problems, you'll see that the

00:13:20.900 --> 00:13:22.530
systematic name way is actually

00:13:22.530 --> 00:13:23.770
pretty, pretty logical.

00:13:23.770 --> 00:13:26.570
And actually, if you have more
than five or six carbons in

00:13:26.570 --> 00:13:29.460
the group, they always or they
tend to always use the

00:13:29.460 --> 00:13:30.710
systematic naming.