Facile synthesis of ethyl 2-arylpropenoates by cross-coupling reaction using electrogenerated highly reactive zinc

Highly reactive zinc metal was prepared by electrolysis of a DMF solution containing naphthalene and a supporting electrolyte in a one-compartment cell fitted with a platinum cathode and a zinc anode. This reactive zinc was used for efficient transformation of ethyl 2-bromoacrylate into the corresponding organozinc compound, which was reacted with various aryl iodides or bromides in the presence of 5 mol% Pd(P(o-Tol)3)2Cl2 to give the corresponding cross-coupling products in high yields. These cross-coupling reactions were successfully applied to a synthesis of the precursor of naproxen and cicloprofen, non-steroidal anti-inflammatory agent.