NaOtBu

Sodium tert-butoxide, commonly abbreviated NaOtBu, is the sodium salt of tert-butanol and is widely used as a strong, hindered base in organic synthesis. Its chemical formula is NaOC(CH3)3, and the tert-butoxide anion is bulky, which lowers nucleophilicity while maintaining high basicity.

NaOtBu is typically encountered as a solid, white or off-white compound. It is hygroscopic and reactive with moisture in air and water, readily hydrolyzing to tert-butanol and sodium hydroxide. For handling and storage, it is kept under dry conditions, often as a solid under inert atmosphere or in an anhydrous solvent system such as THF or tert-butanol solutions to limit degradation.

Commercially, NaOtBu is available in various forms, including dry solid grades and solutions in organic solvents. It is used in a wide range of organic transformations that require a strong, non-nucleophilic base. Its bulky structure favors deprotonation of relatively acidic substrates and minimizes unwanted substitution by nucleophilic attack. Typical applications include the generation of enolates from ketones and esters, deprotonation of weak C–H bonds, and base-promoted eliminations or substitutions where a less hindered base might cause side reactions.

Compared with other bases, NaOtBu offers a balance of high basicity and low nucleophilicity, making it valuable for reactions sensitive to nucleophilic base behavior. It is incompatible with moisture and acids and must be handled with appropriate dry techniques and protective equipment.

Safety notes include irritation potential on contact, corrosivity of the base, and the need to avoid inhalation of dust.