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Catalytic Asymmetric Mannich Reaction of ?-Fluoronitriles with Ketimines: Enantioselective and Diastereodivergent Construction of Vicinal Tetrasubstituted Stereocenters.

ABSTRACT: Diastereodivergent and enantioselective conversion of isatin ketimines to ?-fluoro-?-aminonitriles with vicinal tetrasubstituted stereocenters is achieved by a chiral copper complex/guanidine base catalyzed Mannich reaction with proper choice of the bisphosphine ligand. The reaction is broad in scope, scalable, and provides efficient access to a series of 3-aminoindolinones exhibiting a quaternary carbon-fluorine stereocenter with high yields and stereoselectivities. Selective transformations of the Mannich reaction products into multifunctional 3-aminooxindoles without erosion of enantiomeric and diastereomeric purity highlight the synthetic utility.

SUBMITTER: Ding R

PROVIDER: S-EPMC6449049 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Catalytic Asymmetric Mannich Reaction of α-Fluoronitriles with Ketimines: Enantioselective and Diastereodivergent Construction of Vicinal Tetrasubstituted Stereocenters.

Ding Ransheng R De Los Santos Zeus A ZA Wolf Christian C

ACS catalysis 20190206 3

Diastereodivergent and enantioselective conversion of isatin ketimines to α-fluoro-β-aminonitriles with vicinal tetrasubstituted stereocenters is achieved by a chiral copper complex/guanidine base catalyzed Mannich reaction with proper choice of the bisphosphine ligand. The reaction is broad in scope, scalable, and provides efficient access to a series of 3-aminoindolinones exhibiting a quaternary carbon-fluorine stereocenter with high yields and stereoselectivities. Selective transformations of ...[more]

PMID: 30956891

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