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Atom-Economical Ni-Catalyzed Diborylative Cyclization of Enynes: Preparation of Unsymmetrical Diboronates.

ABSTRACT: We report a Ni-catalyzed diborylative cyclization of enynes that affords carbo- and heterocycles containing both alkyl- and alkenylboronates. The reaction is fully atom-economical, shows a broad scope, and employs a powerful and inexpensive catalytic Ni-based system. The reaction mechanism seems to involve activation of the enyne by Ni(0) through oxidative cyclometalation of the enyne prior to diboron reagent activation. An unprecedented dinuclear bis(organometallic) Ni(I) intermediate complex was isolated.

SUBMITTER: Cabrera-Lobera N

PROVIDER: S-EPMC7196956 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Atom-Economical Ni-Catalyzed Diborylative Cyclization of Enynes: Preparation of Unsymmetrical Diboronates.

Cabrera-Lobera Natalia N Quirós M Teresa MT Brennessel William W WW Neidig Michael L ML Buñuel Elena E Cárdenas Diego J DJ

Organic letters 20190729 16

We report a Ni-catalyzed diborylative cyclization of enynes that affords carbo- and heterocycles containing both alkyl- and alkenylboronates. The reaction is fully atom-economical, shows a broad scope, and employs a powerful and inexpensive catalytic Ni-based system. The reaction mechanism seems to involve activation of the enyne by Ni(0) through oxidative cyclometalation of the enyne prior to diboron reagent activation. An unprecedented dinuclear bis(organometallic) Ni(I) intermediate complex w ...[more]

PMID: 31356084

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