An efficient and selective olefination of aldehydes with ethyl diazoacetate using copper(II) bis-thiazole complex as heterogeneous catalyst

Abstract

The selective olefination of a variety of aromatic aldehydes with the use of ethyl diazoacetate catalyzed by heterogeneous copper(II) complex of 3,5-bis(2–benzothiazolyl)pyridine, [Cu(II)(BTP)(OTf)2], immobilized on silica nanoparticles and chloromethylated polystyrene, [Cu(II)(BTP)(OTf)2]@TMSP-nSiO2, [Cu(II)(BTP)(OTf)2]@CMP, in the presence of triphenylphosphine. These reactions were done in excellent yields (> 85%), with remarkable selectivity for the E-isomer, time of reaction is short, and condition of reaction is mild. The mechanism of olefination was investigated, and the possible pathway is discussed. In this manner, the catalytic activity of the heterogeneous catalyst was investigated, and results showed that we could use this catalyst numerous times, and catalytic activity did not decrease. Graphical abstract: [Figure not available: see fulltext.] © 2022, Iranian Chemical Society.