Practical synthesis of 2-(N-substituted)-aminobenzimidazoles and highly functionalized bicyclic quanidines via CuCl-promoted intramolecular cyclization

ORGN 392

Xiao-jun Wang, Li Zhang, lzhang1@rdg.boehringer-ingelheim.com, Yibo Xu, Dhileepkumar Krishnamurthy, dkrishna@rdg.boehringer-ingelheim.com, and Chris Senanayake. Department of Chemical Development, Boehringer Ingelheim Pharmaceuticals, Inc, 900 Ridgebury Rd., P.O.Box 368, Ridgefield, CT 06877-0368
A novel high yielding and practical Copper-promoted intramolecular cyclization was developed. In this paper, a series of Copper salts had been evaluated and found that CuCl gives the best result. Thus, N-(2-aminoaryl)thioureas undergo CuCl-promoted intramolecular cyclization to give the corresponding 2-(N-substituted amino)benzimidazoles in good to excellent isolated yields without the use of column chromatography and thiohydantoins provide highly functionalized bicyclic guanidines in excellent yields.

 

Bioorganic, Metal-Mediated Reactions, and Molecular Recognition
8:00 PM-10:00 PM, Tuesday, 30 August 2005 Washington DC Convention Center -- Hall A, Poster

Division of Organic Chemistry

The 230th ACS National Meeting, in Washington, DC, Aug 28-Sept 1, 2005