Diastereoselective synthesis of spiro[indene-2,2′-pyrazolo[1,2-a]pyrazoles] and spiro[indoline-3,2′-pyrazolo[1,2-a]pyrazoles] via 1,3-dipolar cycloaddition

Abstract

The 1,3-dipolar cycloaddition of cyclic azomethine imines with 2-arylideneindene-1,3-diones in refluxing acetonitrile afforded predominately cis-1,3-diaryl-substituted spiro[indene-2,2′-pyrazolo[1,2-a]pyrazole] derivatives in good yields. Significantly, the similar cycloaddition reaction of cyclic azomethine imines with 3-phenacylideneoxindoles gave polysubstituted spiro[indoline-3,2′-pyrazolo[1,2-a]pyrazoles] in good yields and with high diastereoselectivity.