2-Imidazolidinone benzofurans as unexpected outcome of the Lewis acid mediated Nenitzescu reaction.

The Lewis acid mediated Nenitzescu reaction with piperazinone enaminoesters surprisingly afforded rearranged 2-imidazolidinone 5-hydroxybenzofurans. The reaction was optimised and a scope study was performed. A one-pot two-step procedure was realised starting directly from 1,2-diaminoethane, diethyl acetylene dicarboxylate and 1,4-benzoquinone. A plausible reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]