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Copper-catalyzed intermolecular C(sp3)-H bond functionalization towards the synthesis of tertiary carbamates.

ABSTRACT: We describe the development of an intermolecular unactivated C(sp3)-H bond functionalization towards the direct synthesis of tertiary carbamates. The transformation proceeded using a readily available, abundant first-row transition metal catalyst (copper), and isocyanates as the source of the amide moiety. This is a novel strategy for direct transformation of a variety of unactivated hydrocarbon feedstocks to N-alkyl-N-aryl and N,N-dialkyl carbamates without pre-functionalization or installation of a directing group. The reaction had a broad substrate scope with 3° > 2° > 1° site selectivity. The reaction proceeded even on a gram scale, and a corresponding free amine was directly obtained when the reaction was performed at high temperature. Kinetic studies suggested that radical-mediated C(sp3)-H bond cleavage was the rate-determining step.

SUBMITTER: Chikkade PK

PROVIDER: S-EPMC5657409 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Copper-catalyzed intermolecular C(sp3)-H bond functionalization towards the synthesis of tertiary carbamates.

Chikkade Prasanna Kumara PK Kuninobu Yoichiro Y Kanai Motomu M

Chemical science 20150323 5

We describe the development of an intermolecular unactivated C(sp3)-H bond functionalization towards the direct synthesis of tertiary carbamates. The transformation proceeded using a readily available, abundant first-row transition metal catalyst (copper), and isocyanates as the source of the amide moiety. This is a novel strategy for direct transformation of a variety of unactivated hydrocarbon feedstocks to N-alkyl-N-aryl and N,N-dialkyl carbamates withou ...[more]

PMID: 29142689

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