Synthesis 2011(8): 1261-1266  
DOI: 10.1055/s-0030-1258476
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

N-Thioaroylmorpholines in Silica Gel-Water: An Efficient System to Access Functionalized Allylic Thioesters from Baylis-Hillman Bromides

Rajesh Patel, Vishnu P. Srivastava, Lal Dhar S. Yadav*
Green Synthesis Lab, Department of Chemistry, University of Allahabad, Allahabad 211 002, India
Fax: +91(532)2460533; e-Mail: ldsyadav@hotmail.com;
Further Information

Publication History

Received 29 December 2010
Publication Date:
14 March 2011 (online)

Abstract

A facile, one-pot synthesis of allylic thioesters starting from Baylis-Hillman (BH) bromides and N-thioaroylmorpholines is described. The synthesis is performed in a silica gel-water system without any additional catalyst or co-catalyst. The reaction pathway involves selective S-alkylation of N-thioaroylmorpholines via nucleophilic displacement (SN2) with BH bromides, followed by hydrolysis to afford the corresponding thioesters. The present synthetic protocol avoids the application of malodorous sulfur compounds of limited accessibility such as thiols, and thioacids and their salts as reactants.