Table of Contents
Organic Chemistry International
Volume 2014 (2014), Article ID 851924, 8 pages
http://dx.doi.org/10.1155/2014/851924
Research Article

Microwave-Assisted Three-Component “Catalyst and Solvent-Free” Green Protocol: A Highly Efficient and Clean One-Pot Synthesis of Tetrahydrobenzo[b]pyrans

Department of Chemistry, Visva-Bharati (A Central University), Santiniketan 731235, India

Received 26 July 2014; Revised 2 September 2014; Accepted 2 September 2014; Published 17 September 2014

Academic Editor: Ashraf Aly Shehata

Copyright © 2014 Sougata Santra et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A green and highly efficient method has been developed for the one-pot synthesis of tetrahydrobenzo[b]pyrans via a three-component condensation of aldehydes, 1,3-cyclic diketones, and malononitrile under MW irradiation without using any catalyst and solvent. This transformation presumably occurs by a sequential Knoevenagel condensation, Michael addition, and intramolecular cyclization. Operational simplicity, solvent and catalyst-free conditions, the compatibility with various functional groups, nonchromatographic purification technique, and high yields are the notable advantages of this procedure.