Tetraethylammonium hydroxide
# Tetraethylammonium hydroxide

Tetraethylammonium hydroxide is the organic compound with the formula $(C_2H_5)_4NOH,$ abbreviated $Et_4NOH.$ It is the tetraethylammonium salt of hydroxide. It is used and dispensed as solutions in water or alcohols, which are colorless and highly alkaline. The compound is a common reagent in organic synthesis. It is also employed in the preparation of zeolites.

## Structure

Tetraethylammonium hydroxide is most commonly encountered as an aqueous solution. Several hydrates $NEt_4OH·xH_2O.$ have been crystallized, including x = 4, 5, 9. These salts feature well separated $Et_4N^+$ cations and hydroxide anions. The hydroxide groups are linked by hydrogen bonds to the water of crystallization. Anhydrous Tetraethylammonium hydroxide has not been isolated.

## Synthesis and reactions

It is prepared from tetraethylammonium bromide by salt metathesis, using a hydroxide-loaded ion exchange column or by the action of silver oxide. Attempted isolation of $Et_4NOH$ induces Hofmann elimination, leading to triethylamine and ethylene.

Treatment of $Et_4NOH$ with a wide range of acids gives water and the other tetraethylammonium salts:

    ${\ce {Et4NOH + HX -> Et4NX + H2O}}$
