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1,n-Bisborylalkanes via Radical Boron Migration.

ABSTRACT: A systematic study of radical boron migration in diboronate complexes to form synthetically valuable 1,n-bisborylalkanes is reported. The boronate complexes are readily generated by reaction of commercial bis(pinacolato)diboron with alkyl Grignard compounds. C-radical generation at a defined position with respect to the diboron moiety is achieved either via intermolecular H-abstraction with a CF3-radical or via alkene perfluoroalkyl radical addition. It is shown that radical 1,2- and 1,4-boron migrations to provide geminal and 1,3-bisborylalkanes are efficient transformations. The 1,5-boron migration in the homologous series leading to 1,4-bisborylalkanes is also occurring, albeit with lower efficiency. Experimental results are supported by DFT calculations which also reveal the corresponding 1,3-boron migration in such diboronate complexes to be feasible.

SUBMITTER: Wang D

PROVIDER: S-EPMC7259776 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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1,n-Bisborylalkanes via Radical Boron Migration.

Wang Dinghai D Mück-Lichtenfeld Christian C Studer Armido A

Journal of the American Chemical Society 20200506 20

A systematic study of radical boron migration in diboronate complexes to form synthetically valuable 1,n-bisborylalkanes is reported. The boronate complexes are readily generated by reaction of commercial bis(pinacolato)diboron with alkyl Grignard compounds. C-radical generation at a defined position with respect to the diboron moiety is achieved either via intermolecular H-abstraction with a CF3-radical or via alkene perfluoroalkyl radical addition. It is shown that radical 1, ...[more]

PMID: 32363871

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