Synthesize of β-Amino Esters from Enamides via 1,8-Diazabicyclo[5.4.0]undecane-7-ene-Mediated Hydroalkylation

A 1,8-diazabicyclo[5.4.0]undecane-7-ene (DBU)-mediated hydroalkylation of enamides with malonic acid diesters/β-carbonyl esters has been established, featuring no metal involvement, mild reaction conditions, and good functional group tolerance. The protocol enables the expedited preparation of a variety of β-amino esters. Preliminary mechanistic investigations, encompassing control experiments and capture experiments of key intermediates, have substantiated the proposed DBU-mediated hydroalkylation pathway.