Bis(imidazolidine)pyridine-NiCl2 Catalyst for Nitro-Mannich Reaction of Isatin-Derived N-Boc Ketimines: Asymmetric Synthesis of Chiral 3-Substituted 3-Amino-2-oxindoles
摘要:
An (S,S)-diphenyldiamine-derived bis(imidazolidine)-pyridine (PyBidine)-NiCl2 complex catalyzed the nitro-Mannich reaction of isatin-derived N-Boc ketimines to construct a chiral quaternary aminocarbon center at the C3 position of oxindoles in yields of up to 99% with 95% ee.