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Enantioselective Radical Construction of 5-Membered Cyclic Sulfonamides by Metalloradical C-H Amination.

ABSTRACT: Both arylsulfonyl and alkylsulfonyl azides can be effectively activated by the cobalt(II) complexes of D2-symmetric chiral amidoporphyrins for enantioselective radical 1,5-C-H amination to stereoselectively construct 5-membered cyclic sulfonamides. In addition to C-H bonds with varied electronic properties, the Co(II)-based metalloradical system features chemoselective amination of allylic C-H bonds and is compatible with heteroaryl groups, producing functionalized 5-membered chiral cyclic sulfonamides in high yields with high enantioselectivities. The unique profile of reactivity and selectivity of the Co(II)-catalyzed C-H amination is attributed to its underlying stepwise radical mechanism, which is supported by several lines of experimental evidence.

SUBMITTER: Hu Y

PROVIDER: S-EPMC6854306 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Enantioselective Radical Construction of 5-Membered Cyclic Sulfonamides by Metalloradical C-H Amination.

Hu Yang Y Lang Kai K Li Chaoqun C Gill Joseph B JB Kim Isaac I Lu Hongjian H Fields Kimberly B KB Marshall McKenzie M Cheng Qigan Q Cui Xin X Wojtas Lukasz L Zhang X Peter XP

Journal of the American Chemical Society 20191101 45

Both arylsulfonyl and alkylsulfonyl azides can be effectively activated by the cobalt(II) complexes of D2-symmetric chiral amidoporphyrins for enantioselective radical 1,5-C-H amination to stereoselectively construct 5-membered cyclic sulfonamides. In addition to C-H bonds with varied electronic properties, the Co(II)-based metalloradical system features chemoselective amination of allylic C-H bonds and is compatible with heteroaryl groups, producing functionalized 5-membered c ...[more]

PMID: 31622088

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