Synthesis 2010(23): 4043-4050  
DOI: 10.1055/s-0030-1258261
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Green Synthesis of Benzopyran-Annulated Thiopyrano[2,3-b]thiochromen-5(4H)-ones by Domino Knoevenagel-Hetero-Diels-Alder Reaction

K. C. Majumdar*, Abu Taher, Sudipta Ponra
Department of Chemistry, University of Kalyani, Kalyani 741235, W. B., India
e-Mail: kcm_ku@yahoo.co.in;
Further Information

Publication History

Received 5 August 2010
Publication Date:
17 September 2010 (online)

Abstract

Benzopyran-annulated thiopyrano[2,3-b]thiochromen-5(4H)-ones have been synthesized by the domino Knoevenagel-hetero-Diels-Alder (DKHDA) reaction of 4-hydroxydithiocoumarin with O-allylated salicylaldehyde and O-propargylated salicyl­aldehyde in aqueous medium. The reaction requires only a single step operation and is highly regio- and stereoselective providing potentially bioactive polycyclic heterocycles in high yields.

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CCDC 778351 contains the supplementary crystallographic data for compound 5a. These data can be obtained free of charge at www.ccdc.cam.ac.uk/conts/retrieving.html [or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(1223)336033,
E-mail: deposit@ccdc.cam.ac.uk].