E-Journal of Chemistry
Volume 8, Issue 2, Pages 798-802
http://dx.doi.org/10.1155/2011/103913
Heteropoly Acid Catalyzed Selective Cyclization of 6-Alkyl-3-propargylmercapto-1,2,4-triazin-5(2H)-one
1Department of Chemistry, Islamic Azad University Mashhad Branch, Mashhad, Iran
2Department of Chemistry, Islamic Azad University Yazd Branch, Yazd, Iran
3Department of Chemistry, School of Sciences, Azzahra University, Tehran, Iran
Received 9 June 2010; Accepted 27 August 2010
Copyright © 2011 Hindawi Publishing Corporation. 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
Cyclization of 6-alkyl-3-propargylmercapto-1,2,4-triazin-5(2H)-one, derivatives (2) in the presence of Keggin heteropoly acids, H3PW1212O40, H3PMo12O40, H4SiW12O40 and lacunary Keggin structure (K7PMo2W9O40) afforded 3 (3a = 6-dimethyl-7H-thiazolo[2,3-b][1,2,4]-triazin-7-one and 3b=6-ethyl-3-methyl-7H-thiazolo[2,3-b][1,2,4]-triazin-7-one) in high yields and short reaction times