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Chemoselective amination of propargylic C(sp³)-H bonds by cobalt(II)-based metalloradical catalysis.

ABSTRACT: Highly chemoselective intramolecular amination of propargylic C(sp(3))-H bonds has been demonstrated for N-bishomopropargylic sulfamoyl azides through cobalt(II)-based metalloradical catalysis. Supported by D(2h)-symmetric amidoporphyrin ligand 3,5-Di(t)Bu-IbuPhyrin, the cobalt(II)-catalyzed C-H amination proceeds effectively under neutral and nonoxidative conditions without the need of any additives, and generates N2 as the only byproduct. The metalloradical amination is suitable for both secondary and tertiary propargylic C-H substrates with an unusually high degree of functional-group tolerance, thus providing a direct method for high-yielding synthesis of functionalized propargylamine derivatives.

SUBMITTER: Lu H

PROVIDER: S-EPMC4119425 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Chemoselective amination of propargylic C(sp³)-H bonds by cobalt(II)-based metalloradical catalysis.

Lu Hongjian H Li Chaoqun C Jiang Huiling H Lizardi Christopher L CL Zhang X Peter XP

Angewandte Chemie (International ed. in English) 20140519 27

Highly chemoselective intramolecular amination of propargylic C(sp(3))-H bonds has been demonstrated for N-bishomopropargylic sulfamoyl azides through cobalt(II)-based metalloradical catalysis. Supported by D(2h)-symmetric amidoporphyrin ligand 3,5-Di(t)Bu-IbuPhyrin, the cobalt(II)-catalyzed C-H amination proceeds effectively under neutral and nonoxidative conditions without the need of any additives, and generates N2 as the only byproduct. The metalloradical amination is suitable for both secon ...[more]

PMID: 24840605

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