An Efficient Cobalt(<scp>I</scp>)‐Catalysed Reformatsky Reaction using α‐Chloro Esters

Abstract

Abstract An efficient cobalt( I )‐catalysed Reformatsky reaction using α‐chloro esters has been developed. The catalyst is prepared by reducing the cobalt( II ) chloride (5 %)/1,2‐bis(diphenylphosphino)ethane (dppe)(5 %)/zinc iodide (10 %) system with zinc metal in acetonitrile in the presence of both the α‐chloro ester and the carbonyl compound; good to excellent conversions to β‐hydroxy esters are obtained at room temperature in 2.5 h.