Frustrated Lewis Pair (FLP)-Catalyzed Hydrogenation of Aza-Morita− Baylis−Hillman Adducts and Sequential Organo-FLP Catalysis

نویسندگان

  • Imtiaz Khan
  • Mattia Manzotti
  • Graham J. Tizzard
  • Simon J. Coles
  • Rebecca L. Melen
  • Louis C. Morrill
چکیده

Herein we report the metal-free diastereoselective frustrated Lewis pair (FLP)-catalyzed hydrogenation of azaMorita−Baylis−Hillman (aza-MBH) adducts, accessing a diverse range of stereodefined β-amino acid derivatives in excellent isolated yields (28 examples, 89% average yield, up to 90:10 d.r.). Furthermore, sequential organo-FLP catalysis has been developed. An initial organocatalyzed aza-MBH reaction followed by in situ FLP formation and hydrogenation of the electrondeficient α,β-unsaturated carbonyl compounds can be performed in one-pot, using DABCO as the Lewis base in both catalytic steps.

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تاریخ انتشار 2017