Catalytic asymmetric synthesis of γ-hydroxy ketones and aromatic hydroxy ketones by the chemo- and enantio-selective alkylation of keto aldehydes with dialkylzincs

Abstract

Optically active γ-hydroxy ketones and aromatic hydroxy ketones with high (up to 96%) enantiomeric excesses have been synthesized by the chemo- and enantio-selective addition of dialkylzincs to γ-keto aldehydes and aromatic keto aldehydes, respectively, using N,N-dibutylnorephedrine (DBNE)1 and (1-methylpyrrolidin-2-yl)diphenylmethanol (DPMPM)5 as chiral catalysts. The method provides a non-homoaldol approach to optically active γ-hydroxy ketones.