Synthesis of 3-Aminopyrrolo[2,1-a]isoquinoline, 3-Aminopyrrolo[2,1-a]phthalazine, and 7-Aminopyrrolo[1,2-b]pyridazine Derivatives

A simple route to 3-aminopyrrolo[2,1-a]isoquinoline, 3-aminopyrrolo[2,1-a]phthalazine, and 7-aminopyrrolo[1, 2-b]pyridazine derivatives 8a, 8b and 11, respectively, is described, based on displacement of a chlorine atom in the appropriate precursors with benzylamine. The chloro-substituted precursors were prepared by using a tandem dichlorocarbene/cycloimmonium ylide approach.