<unk> , often just called<unk> , is a clear, colorless heterocyclic organic compound which is a liquid at room temperature and pressure.  It has the molecular formula C4H8O2 and a boiling point of 101°C.  It is commonly used as an aprotic solvent.<unk>  has a weak smell similar to that of diethyl ether.  There are also two other less common isomeric compounds,<unk>  and<unk> . <unk>  is a peroxide which forms naturally in old bottles of tetrahydrofuran.<unk>  is classified as an ether, with each of its two oxygen atoms forming an ether functional group.  It is more polar than diethyl ether, which also has four carbons, but only one ether functional group.  Diethyl ether is rather insoluble in water, but<unk>  is miscible with water and is hygroscopic.  Its higher polarity and slightly higher molecular mass also gives it a substantially higher boiling point than diethyl ether.  When used as a solvent for a grignard reaction,<unk>  favorably affects the formation of magnesium halide salts in the Schlenk equilibrium.
The name<unk>  should not be confused with dioxin, which is a different compound but is also a diether (two ether functional groups).
1,4-Dioxane
Dihydrotachysterol
Cholesteryl ester
Squalene
Arachidonic acid
Choline c-11
Eicosanoid
Ramogen