A General, One-Step Synthesis of α-Keto Esters

Abstract Several new multi-step methods for the synthesis of α-keto esters have been reported recently which are based on the addition of alkyl lithium reagents to triethoxyacetonitrile1, the reaction of Grignard reagents with ethy1 α-oxo-1H-imidazole-1-acetate2, the alcoholysis of acy1 cyanides3, the acylation of mercaptal anions with ethy1 chloroformate4, the alkylation of 1,3-dithiane-2-carboxylate under homogeneous5 or under phase transfer conditions6 and the addition of the methyl methylthiomethyl sulfoxide anion to nitriles7. These novel methods lack the convenience of the direct addition of Grignard reagents to diethyl oxalate: