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Synthesis of Stereodefined 1,1-Diborylalkenes via Copper-Catalyzed Diboration of Terminal Alkynes.

ABSTRACT: A copper-catalyzed method for the E-selective 1,1-diboration of terminal alkynes is described. The tandem process involves sequential dehydrogenative borylation of the alkyne substrate with HBdan (1,8-diaminonaphthalatoborane), followed by hydroboration with HBpin (pinacolborane). This method proceeds efficiently under mild conditions, furnishing 1,1-diborylalkenes with excellent stereoselectivity and broad functional group tolerance. Taking advantage of the different reactivities of the two boryl moieties, the products can then be employed in stepwise cross-couplings with aryl halides for the stereocontrolled construction of trisubstituted alkenes.

SUBMITTER: Gao Y

PROVIDER: S-EPMC7391966 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Synthesis of Stereodefined 1,1-Diborylalkenes via Copper-Catalyzed Diboration of Terminal Alkynes.

Gao Yang Y Wu Zhong-Qian ZQ Engle Keary M KM

Organic letters 20200623 13

A copper-catalyzed method for the <i>E</i>-selective 1,1-diboration of terminal alkynes is described. The tandem process involves sequential dehydrogenative borylation of the alkyne substrate with HBdan (1,8-diaminonaphthalatoborane), followed by hydroboration with HBpin (pinacolborane). This method proceeds efficiently under mild conditions, furnishing 1,1-diborylalkenes with excellent stereoselectivity and broad functional group tolerance. Taking advantage of the different reactivities of the ...[more]

PMID: 32574499

Similar Datasets

Cobalt-Catalyzed 1,1-Diboration of Terminal Alkynes: Scope, Mechanism, and Synthetic Applications.

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Hydroboration of Terminal Alkenes and trans-1,2-Diboration of Terminal Alkynes Catalyzed by a Manganese(I) Alkyl Complex.

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