New One Pot and Efficient Four‐Components Reaction for Synthesis of 2,3‐Dihydrothiophene Carbamate Derivatives

Abstract

A new series of 2,3-dihydrothiophenes bearing ethyl carbamate moiety (4 a-4 l) was designed and synthesized through a facile synthetic route involving domino ring-opening/recyclization reaction of 1,3-thiazolidinedione. The synthesis was achieved via a novel one-pot four-component reaction of aromatic aldehydes, malononitrile and 1,3-thiazolidinedione, using 4dimethylaminopyridine as base catalyst under ethanol reflux.The molecular structures of the synthesized compounds were elucidated by usual spectroscopic techniques such as FT-IR, 1 H NMR, 13 C NMR and HRMS methods. X-ray diffraction was used to confirm the structures of compounds 4 d and 4 j. Readily available starting materials, atom-efficient routes employing more mild reaction conditions and environmentally benign are the attracting features of this current protocol.