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 SN Ar 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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