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Selective Benzylic CH-Borylations by Tandem Cobalt Catalysis.

ABSTRACT: Metal-catalyzed C-H activations are environmentally and economically attractive synthetic strategies for the construction of functional molecules as they obviate the need for pre-functionalized substrates and minimize waste generation. Great challenges reside in the control of selectivities, the utilization of unbiased hydrocarbons, and the operation of atom-economical dehydrocoupling mechanisms. An especially mild borylation of benzylic CH bonds was developed with the ligand-free pre-catalyst Co[N(SiMe₃ )₂ ]₂ and the bench-stable and inexpensive borylation reagent B₂ pin₂ that produces H₂ as the only by-product. A full set of kinetic, spectroscopic, and preparative mechanistic studies are indicative of a tandem catalysis mechanism of CH-borylation and dehydrocoupling via molecular Co^I catalysts.

SUBMITTER: Ghosh P

PROVIDER: S-EPMC9299014 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Selective Benzylic CH-Borylations by Tandem Cobalt Catalysis.

Ghosh Pradip P Schoch Roland R Bauer Matthias M Jacobi von Wangelin Axel A

Angewandte Chemie (International ed. in English) 20211122 1

Metal-catalyzed C-H activations are environmentally and economically attractive synthetic strategies for the construction of functional molecules as they obviate the need for pre-functionalized substrates and minimize waste generation. Great challenges reside in the control of selectivities, the utilization of unbiased hydrocarbons, and the operation of atom-economical dehydrocoupling mechanisms. An especially mild borylation of benzylic CH bonds was developed with the ligand-free pre-catalyst C ...[more]

PMID: 34596960

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