Synthesis of (E)-nitroalkenes Catalysed by Ethanolamine Supported on Silica

Abstract

A simple method for preparing (E)-nitroalkenes based on a Henry reaction in the presence of a heterogenized homogeneous catalyst consisting of silica-supported ethanolamine is proposed. With 4-substituted benzaldehydes, the reaction gives the corresponding (E)-nitrostyrenes in high yields and a short time. Heterocyclic carboxaldehydes also give good results, but the presence of an N or S atom in the ring has a slightly adverse effect on the reaction. The synthetic process is quite novel and interesting. The catalyst remains active and exhibits no substantial loss of activity or selectivity over up to three reaction cycles.

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