Pyrrolidine-Mediated Direct Preparation of (E)-Monoarylidene Derivatives of Homo- and Heterocyclic Ketones with Various Aldehydes

Abstract

An efficient method for the facile synthesis of (E)-monoarylidene derivatives of homo-And heterocyclic ketones with various aldehydes in the presence of a pyrrolidine organocatalyst has been achieved. A range of a,β-unsaturated ketones were obtained in moderate to high yields (up to 99%). Unlike the Claisen-Schmidt condensation process, the formation of undesired bisarylidene byproducts is not observed. The possible reaction mechanism suggests that the reaction proceeds via a Mannich-elimination sequence. © 2014 by the authors; licensee MDPI, Basel, Switzerland.