An original route to 2-alkyamino-4-phenylquinazolines in three steps from simple (hetero)aromatic amines is reported here. The key step involves the intramolecular cyclization of benzoyl arylguanidines performed in [OMIm]Cl ionic liquid. The basic (hetero)aromatic guanidines deprotonate the imidazolium-based ionic liquid, thus triggering the cascade process ultimately leading to the intramolecular cyclization. This reaction is the first example of a Friedel-Crafts-type reaction in which an N-heterocyclic carbene is involved in the formation of the electrophilic intermediate.

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http://dx.doi.org/10.1021/jo902726kDOI Listing

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