Microwave-Assisted Benzimidazole Cyclization by Bismuth Chloride

Yuh-Sheng Su; Chung-Ming Sun

doi:10.1055/s-2005-865240

LETTER

Microwave-Assisted Benzimidazole Cyclization by Bismuth Chloride

Yuh-Sheng Su, Chung-Ming Sun*
Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan
Fax: +886(3)5723764; e-Mail: cmsun@mail.nctu.edu.tw;

Abstract

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Abstract

We have developed a multi-step, microwave-assisted method for the bismuth chloride catalyzed synthesis of 1,2-disubstituted benzimidazoles. Biologically interesting benzimidazoles were readily assembled using a S_NAr reaction, reduction, and finally a bismuth(III)-mediated cyclization under microwave irradiation. The desired products were then liberated from the soluble matrix in excellent yield and purity after cleavage. Each step of the synthetic sequence was performed under microwave conditions.

Key words

bismuth chloride - combinatorial chemistry - liquid-phase method - microwave assisted synthesis - scaffold

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References

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