Cu-Catalyzed Direct Enantioselective Vinylogous Mannich Reaction between β,γ-Unsaturated Pyrazoleamides and Ketimines
Ling-Shan Luo1, Si-Meng Hou1, Jian Lu1
1Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai 200237, P. R. China.
Abstract:
A catalytic asymmetric vinylogous Mannich-type reaction between β,γ-unsaturated amides and ketimines has been developed in excellent regio-, diastereo-, and enantioselectivities. The methodology provides an efficient approach to construct chiral homoallylic amines with a 3-amino-2-oxindole scaffold. Moreover, the transformations of the chiral products, including the removal of the pyrazole group or Boc group, the reduction of the C-C double bond, and Suzuki coupling, have been investigated.
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