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Copper-Catalyzed Triboration of Terminal Alkynes Using B₂ pin₂ : Efficient Synthesis of 1,1,2-Triborylalkenes.

ABSTRACT: We report herein the catalytic triboration of terminal alkynes with B₂ pin₂ (bis(pinacolato)diboron) using readily available Cu(OAc)₂ and Pⁿ Bu₃ . Various 1,1,2-triborylalkenes, a class of compounds that have been demonstrated to be potential matrix metalloproteinase (MMP-2) inhibitors, were obtained directly in moderate to good yields. The process features mild reaction conditions, a broad substrate scope, and good functional group tolerance. This copper-catalyzed reaction can be conducted on a gram scale to produce the corresponding 1,1,2-triborylalkenes in modest yields. The utility of these products was demonstrated by further transformations of the C-B bonds to prepare gem-dihaloborylalkenes (F, Cl, Br), monohaloborylalkenes (Cl, Br), and trans-diaryldiborylalkenes, which serve as important synthons and have previously been challenging to prepare.

SUBMITTER: Liu X

PROVIDER: S-EPMC6972586 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Copper-Catalyzed Triboration of Terminal Alkynes Using B2 pin2 : Efficient Synthesis of 1,1,2-Triborylalkenes.

Liu Xiaocui X Ming Wenbo W Friedrich Alexandra A Kerner Florian F Marder Todd B TB

Angewandte Chemie (International ed. in English) 20191119 1

We report herein the catalytic triboration of terminal alkynes with B2 pin2 (bis(pinacolato)diboron) using readily available Cu(OAc)2 and Pn Bu3 . Various 1,1,2-triborylalkenes, a class of compounds that have been demonstrated to be potential matrix metalloproteinase (MMP-2) inhibitors, were obtained directly in moderate to good yields. The process features mild reaction conditions, a broad substrate scope, and good functional group toleranc ...[more]

PMID: 31502712

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