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Branch-Selective Addition of Unactivated Olefins into Imines and Aldehydes.

ABSTRACT: Radical hydrofunctionalization occurs with ease using metal-hydride hydrogen atom transfer (MHAT) catalysis to couple alkenes and competent radicalophilic electrophiles. Traditional two-electron electrophiles have remained unreactive. Herein we report the reductive coupling of electronically unbiased olefins with imines and aldehydes. Iron catalysis allows addition of alkyl-substituted olefins into imines through the intermediacy of free radicals, whereas a combination of catalytic Co(Sal t-Bu, t-Bu) and chromium salts enables a branch-selective coupling of olefins and aldehydes through the formation of a putative alkyl chromium intermediate.

SUBMITTER: Matos JLM

PROVIDER: S-EPMC6469987 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Branch-Selective Addition of Unactivated Olefins into Imines and Aldehydes.

Matos Jeishla L M JLM Vásquez-Céspedes Suhelen S Gu Jieyu J Oguma Takuya T Shenvi Ryan A RA

Journal of the American Chemical Society 20181129 49

Radical hydrofunctionalization occurs with ease using metal-hydride hydrogen atom transfer (MHAT) catalysis to couple alkenes and competent radicalophilic electrophiles. Traditional two-electron electrophiles have remained unreactive. Herein we report the reductive coupling of electronically unbiased olefins with imines and aldehydes. Iron catalysis allows addition of alkyl-substituted olefins into imines through the intermediacy of free radicals, whereas a combination of catalytic Co(Sal <sup>t ...[more]

PMID: 30463404

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