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Aromatic C-H addition of ketones to imines enabled by manganese catalysis.

ABSTRACT: Selectivity control of varied C-H bonds in a complex molecule is a long-standing goal and still a great challenge in C-H activation field. Most often, such selectivity is achieved by the innate reactivity of different C-H bonds. In this context, the classic Mannich reaction of acetophenone derivatives and imines is ascribed to the more reactive C(sp3)-H bonds ? to the carbonyl, with the much less reactive aromatic C(sp2)-H bonds remaining intact. Herein we report an aromatic C(sp2)-H addition of ketones to imines enabled by manganese catalysis, which totally reverses the innate reactivity of C-H bonds ? to the carbonyl and those on the aromatic ring. Diverse products of ortho-C-H aminoalkylated ketones, cyclized exo-olefinic isoindolines, and three-component methylated isoindolines can be successfully accessed under mild reaction conditions, which significantly expands the synthetic utilities of ketones as simple bulk chemicals.

SUBMITTER: Zhou B

PROVIDER: S-EPMC5660118 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Aromatic C-H addition of ketones to imines enabled by manganese catalysis.

Zhou Bingwei B Hu Yuanyuan Y Liu Ting T Wang Congyang C

Nature communications 20171027 1

Selectivity control of varied C-H bonds in a complex molecule is a long-standing goal and still a great challenge in C-H activation field. Most often, such selectivity is achieved by the innate reactivity of different C-H bonds. In this context, the classic Mannich reaction of acetophenone derivatives and imines is ascribed to the more reactive C(sp<sup>3</sup>)-H bonds α to the carbonyl, with the much less reactive aromatic C(sp<sup>2</sup>)-H bonds remaining intact. Herein we report an aromati ...[more]

PMID: 29079807

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