A General and Mild Catalytic alpha-Alkylation of Unactivated Esters Using Alcohols

Catalytic alpha-alkylation of esters with primary alcohols is a desirable process because it uses low-toxicity agents and generates water as the by-product. Reported herein is a NCP pincer/Ir catalyst which is highly efficient for alpha-alkylation of a broad scope of unactivated esters under mild reaction conditions. For the first time, alcohols alkylate unactivated a-substituted acyclic esters, lactones, and even methyl and ethyl acetates. This method can be applied to the synthesis of carboxylic acid derivatives with diverse structures and functional groups, some of which would be impossible to access by conventional enolate alkylations with alkyl halides.