PAPER	Synthesis 2006: 3715-3726   DOI: 10.1055/s-2006-950289
© Georg Thieme Verlag Stuttgart · New York
Synthesis of Fused Imidazoles and Benzothiazoles from (Hetero)Aromatic ortho-Diamines or ortho-Aminothiophenol and Aldehydes Promoted by Chlorotrimethylsilane
Sergey V. Ryabukhina,b, Andrey S. Plaskona,b, Dmitriy M. Volochnyuk*a,c, Andrey A. Tolmachevb
a Enamine Ltd., 23 A. Matrosova st., 01103 Kiev, Ukraine b National Taras Shevchenko University, 62 Volodymyrska st., Kyiv-33, 01033 Kiev, Ukraine c Institute of Organic Chemistry, National Academy of Sciences of Ukraine, Murmanska 5, Kyiv-94, 02094 Kiev, Ukraine Fax: +380(44)5373253; e-Mail: D.Volochnyuk@enamine.net;
Received 12 June 2006

Abstract

New convenient conditions for benzimidazole and benzothiazole syntheses are described. A set of benzimidazoles, 3H-imidazo[4,5-b]pyridines, purines, xanthines and benzothiazoles was readily prepared from (hetero)aromatic ortho-diamines or ortho-aminothiophenol and aldehydes using chlorotrimethylsilane in DMF as a promoter and water-acceptor agent, followed by oxidation with air oxygen.

Key words

benzimidazoles - benzothiazoles - aldehydes - chlorotrimethylsilane - parallel synthesis