Tetrabutylammonium hydroxide is a chemical compound with the formula (C<sub>4</sub>H<sub>9</sub>)<sub>4</sub>NOH, abbreviated Bu<sub>4</sub>NOH with the acronym TBAOH or TBAH. This species is employed as a solution in water or alcohols. It is a common base in organic chemistry. Relative to more conventional inorganic bases, such as KOH and NaOH, Bu<sub>4</sub>NOH is more soluble in organic solvents.
Preparation and reactions
Solutions of Bu<sub>4</sub>NOH are usually prepared in situ from butylammonium halides, Bu<sub>4</sub>NX. For example, by reacting them with silver oxide or using an ion exchange resin. Attempts to isolate Bu<sub>4</sub>NOH induces Hofmann elimination, leading to Bu<sub>3</sub>N and 1-butene. Solutions of Bu<sub>4</sub>NOH are typically contaminated with Bu<sub>3</sub>N for this reason. Similarly, neutralization of Bu<sub>4</sub>NOH with hydrofluoric acid affords a relatively water-free Bu<sub>4</sub>NF. This salt dissolves in organic solvents and is useful in desilylation.