A highly regioselective synthesis of tetrahydropyrrolo1,2-]uinazolin-5(1)one derivatives was achieved by reacting cyclopropane aldehydes with '-aryl anthranil hydrazides in the presence of -toluene sulfonic acid (PTSA). The transformation involves domino imine formation and intramolecular cyclization to form 2-arylcyclopropyl-2,3-dihydroquinolin-4(1)-one, followed by nucleophilic ring opening of the cyclopropyl ring to form desired tetrahydropyrrolo[1,2-]quinazolin-5(1)one in good to excellent yield with complete regioselectivity. This protocol tolerates a great variety of functional groups and thus provides a simple and step-efficient method for pyrroloquinazolinone synthesis.

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http://dx.doi.org/10.1021/acs.joc.9b03170DOI Listing

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