Synthesis of Pyrazolidin‐3‐one Derivatives Bearing Trifluoromethyl Group via Cascade Michael/Intramolecular Transamidation Reactions

Abstract

The cascade Michael/intramolecular transamidation reactions of 3‐phenacylidene‐2‐indolinone derivatives bearing a trifluoromethyl group as a novel Michael acceptor with hydrazines yielded the corresponding pyrazolidin‐3‐one derivatives in good to high yields with excellent diastereoselectivity. These pyrazolidin‐3‐one derivatives, bearing trifluoromethyl groups, can be further transformed into various valuable heterocyclic compounds.