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Rhodium-Catalyzed Enantioselective Radical Addition of CX4 Reagents to Olefins.

ABSTRACT: We describe the synthetically useful enantioselective addition of Br-CX3 (X=Cl or Br) to terminal olefins to introduce a trihalomethyl group and generate optically active secondary bromides. Computational and experimental evidence supports an asymmetric atom-transfer radical addition (ATRA) mechanism in which the stereodetermining step involves outer-sphere bromine abstraction from a [(bisphosphine)RhII BrCl] complex by a benzylic radical intermediate. This mechanism appears unprecedented in asymmetric catalysis.

SUBMITTER: Chen B

PROVIDER: S-EPMC5672916 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Rhodium-Catalyzed Enantioselective Radical Addition of CX4 Reagents to Olefins.

Chen Bo B Fang Cheng C Liu Peng P Ready Joseph M JM

Angewandte Chemie (International ed. in English) 20170614 30

We describe the synthetically useful enantioselective addition of Br-CX3 (X=Cl or Br) to terminal olefins to introduce a trihalomethyl group and generate optically active secondary bromides. Computational and experimental evidence supports an asymmetric atom-transfer radical addition (ATRA) mechanism in which the stereodetermining step involves outer-sphere bromine abstraction from a [(bisphosphine)RhII BrCl] complex by a benzylic radical intermediate. This mechanism appear ...[more]

PMID: 28544237

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