Sodium triacetoxyborohydride, also known as sodium triacetoxyhydroborate, commonly abbreviated STAB, is a chemical compound with the formula Na[(CH3COO)3BH]. Like other borohydrides, it is used as a reducing agent in organic synthesis. It is a white powder with a density of 1.20 g/cm3 and a melting point of 116 to 120 °C (241 to 248 °F; 389 to 393 K). Sodium triacetoxyborohydride is a milder reducing agent than sodium borohydride or even sodium cyanoborohydride. It reduces aldehydes but not most ketones. It is especially suitable for reductive aminations of aldehydes and ketones. However, unlike sodium cyanoborohydride, the triacetoxyborohydride hydrolyzes readily, nor is it compatible with methanol. It reacts only slowly with ethanol and isopropanol and can be used with these. Sodium triacetoxyborohydride is a hydride reagent used in stereoselective reductive amination. It is able to replace toxic sodium cyanoborohydride under most conditions. It is selective in reducing aldehydes to alcohols in the presence of ketones
stab; Sodium triacetoborohydride; Sodium Triacetoxyborohyride; SODIUM TRIACETOXYHYDROBORATE; sodiumtriacetoxyborohydride,calselect?stab; Sodium triacetohydroborate, Triacetohydroborate sodium salt; Sodium; Sodium 1-[(diacetoxyboryl)oxy]ethanolate; Boric acid (H3BO3), diacetyl 1-hydroxyethyl ester, sodium salt (1:1);
reductive amination mechanism sodium triacetoxyborohydride CAS 56553-60-7
The reductive amination mechanism using sodium triacetoxyborohydride involves the conversion of an aldehyde or ketone and an amine into an amine product. Here is a step-by-step explanation of the mechanism:
Formation of imine: The reaction begins with the condensation of the carbonyl compound (aldehyde or ketone) and the amine to form an imine intermediate. This step involves the nucleophilic attack of the amine on the carbonyl carbon, resulting in the loss of a water molecule.
Reduction of imine: Sodium triacetoxyborohydride (NaBH(OAc)₃) serves as the reducing agent in this reaction. It donates a hydride ion (H-) to the imine intermediate, leading to the formation of a secondary amine.
Hydrolysis: The final step involves the hydrolysis of the boron-containing byproduct, which is formed during the reduction step. This hydrolysis can be achieved by adding water or an acid to the reaction mixture. It results in the release of borate species and acetic acid.
Overall, the reductive amination mechanism using sodium triacetoxyborohydride proceeds through the formation of an imine intermediate followed by its reduction to yield the desired amine product. The use of sodium triacetoxyborohydride as a mild reducing agent allows for selective reduction without affecting other functional groups present in the molecule.
sodium triacetoxyborohydride decomposition
Sodium triacetoxyborohydride is a reducing agent used in organic synthesis. It is a colorless salt that is prepared by protonolysis of sodium borohydride with acetic acid. It is a milder reducing agent than sodium borohydride or even sodium cyanoborohydride. It reduces aldehydes but not most ketones. It is especially suitable for reductive aminations of aldehydes and ketones
sodium triacetoxyborohydride mechanism
It is selective in reducing aldehydes to alcohols in the presence of ketones. STAB is also stable in anhydrous acids, which enables reductive amination of aldehydes and ketones. It used in reductive amination of ketones and aldehydes and reductive amination/lactamization of carbonyl compounds with amines.