O-モノアシル酒石酸触媒によるホウ素化合物の活性化

抄録

Activation of boronic acids or related compounds by chiral organocatalysts has emerged as efficient methods for construction of optically active organic molecules. Although several effective organocatalysts such as 3,3’-disubstituted binaphthols or thiourea derivatives have been developed to promote 1,2- or 1,4-addition to (conjugated) carbonyl compounds or imines, such reports are still limited. It is known that α-hydroxycarboxylic acids smoothly react with boronic acids to generate dioxaborolanones having high Lewis acidity. We hypothesized that the dioxaborolanone formation would prompt the activation of B-C bonds and formation of new C-C bond, and found that O-monoacylated tartaric acids (MAT) effectively catalyze 1,4-additions of boronic acids or bis(neopentyl glycolato)diboron to α,β-unsaturated ketones (enones). This article describes development and application of MAT catalysts.