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Reduction of a dihydroboryl cation to a boryl anion and its air-stable, neutral hydroboryl radical through hydrogen shuttling.

ABSTRACT: The addition of Lewis bases to a cyclic (alkyl)(amino)carbene (CAAC)-supported dihydroboron triflate yields the mixed doubly base-stabilised dihydroboryl cations [(CAAC)BH2L]+. Of these, [(CAAC)2BH2]OTf (OTf = triflate) underwent facile two-electron reduction with KC8 owing to a 1,2-hydride migration from boron to the carbene carbon to yield a stable hydroboryl anion. One-electron oxidation of the latter yielded the first neutral hydroboryl radical, which is bench-stable in the solid state.

SUBMITTER: Hagspiel S

PROVIDER: S-EPMC7069503 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Reduction of a dihydroboryl cation to a boryl anion and its air-stable, neutral hydroboryl radical through hydrogen shuttling.

Hagspiel Stephan S Arrowsmith Merle M Fantuzzi Felipe F Hermann Alexander A Paprocki Valerie V Drescher Regina R Krummenacher Ivo I Braunschweig Holger H

Chemical science 20191125 2

The addition of Lewis bases to a cyclic (alkyl)(amino)carbene (CAAC)-supported dihydroboron triflate yields the mixed doubly base-stabilised dihydroboryl cations [(CAAC)BH2L]+. Of these, [(CAAC)2BH2]OTf (OTf = triflate) underwent facile two-electron reduction with KC8 owing to a 1,2-hydride migration from boron to the carbene carbon to yield a stable hydroboryl anion. One-electron oxidation of the latter yielded the first neutral hydroboryl ...[more]

PMID: 32206272

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