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

摘要

A new series of 2,3-dihydrothiophenes bearing ethyl carbamate moiety(4a-4l)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 4-dimethylaminopyridine as base catalyst under ethanol reflux.The molecular structures of the synthesized compounds were elucidated by usual spectroscopic techniques such as FT-IR,1H NMR,~(13)C NMR and HRMS methods.X-ray diffraction was used to confirm the structures of compounds 4d and 4j.Readily available starting materials,atom-efficient routes employing more mild reaction conditions and environmentally benign are the attracting features of this current protocol.