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An Umpolung Strategy for the Synthesis of ?-Aminoketones via Copper-Catalyzed Electrophilic Amination of Cyclopropanols.

ABSTRACT: A novel copper-catalyzed electrophilic amination of cyclopropanols with O-benzoyl-N,N-dialkylhydroxylamines to synthesize various ?-aminoketones via a sequence that includes C-C bond cleavage and Csp(3)-N bond formation is reported. The reaction conditions are mild and tolerate a wide range of functional groups including benzoate, tosylate, expoxide, and ?,?-unsaturated carbonyls, which are incompatible in the traditional amine nucleophilic conjugate addition and the Mannich reaction conditions. Preliminary mechanistic studies and a proposed catalytic cycle of this umpolung ?-aminoketone synthesis process have been described as well.

SUBMITTER: Ye Z

PROVIDER: S-EPMC4690534 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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An Umpolung Strategy for the Synthesis of β-Aminoketones via Copper-Catalyzed Electrophilic Amination of Cyclopropanols.

Ye Zhishi Z Dai Mingji M

Organic letters 20150417 9

A novel copper-catalyzed electrophilic amination of cyclopropanols with O-benzoyl-N,N-dialkylhydroxylamines to synthesize various β-aminoketones via a sequence that includes C-C bond cleavage and Csp(3)-N bond formation is reported. The reaction conditions are mild and tolerate a wide range of functional groups including benzoate, tosylate, expoxide, and α,β-unsaturated carbonyls, which are incompatible in the traditional amine nucleophilic conjugate addition and the Mannich reaction conditions. ...[more]

PMID: 25885943

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