A synthetic route toward α,α-dialkyl α-amino ester derivatives via radical addition to hydrazone derivatives of α-ketoesters under “on-water” conditions

Abstract

Herein, radical addition to the CN bond in hydrazone derivatives of α-ketoesters under “on-water” conditions has been described. The present method provides a route to synthesize α,α-dialkyl α-amino esters, which are difficult to obtain using other methods because of their intrinsically low activity. The radical addition reaction is more efficient when performed under “on-water” conditions than when performed in an organic solvent, showing the prominent solvent effect of water. In the present process, the (Z)-hydrazone derivatives of α-ketoesters show higher reactivity than their corresponding (E)-hydrazones. The process provides tin-free, green reaction conditions.