Hexafluoroisopropanol Catalyzed Ring‐Opening‐Cyclization of Donor−Acceptor Cyclopropanes with Primary Amines

We reveal here a metal-free, ring-opening-cyclization of donor-acceptor cyclopropanes with primary amines to synthesize functionalized dihydropyrroles. This protocol avoids inert conditions and solvents promoted by hexafluoroisopropanol (HFIP).   The reaction is quite general with aryl, alkyl, and alicyclic amines. A good number of cyclopropanes bearing keto groups reacted excellently to produce the desired products. Further, we complemented this method with Meldrum's acid-derived cyclopropanes for synthesizing g-lactams. We have demonstrated the post-synthetic applications of the products and gram-scale synthesis to highlight the adaptability of this synthetic protocol.