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Generation of 1,2-azaboretidines via reduction of ADC borane adducts.

ABSTRACT: Reaction of the acyclic (diamino)carbene (ADC) :C(NiPr2)2 (1) with different dihaloboranes of the type RBX2 (R = Mes, Dur; X = Cl, Br) smoothly afforded a novel class of ADC-stabilized borane adducts. For MesBBr2 however, the reaction did not stop at the adduct level, but an uncommon rearrangement process occurred, which eventually resulted in the formation of a 5-membered boracycle after elimination of mesitylene. Chemical reduction of the ADC borane adducts by KC8 selectively yielded air stable 1,2-azaboretidines. Detailed DFT studies suggest a reduction mechanism involving a highly reactive borylene intermediate, which is converted into the boracycles via a rearrangement/C-H activation sequence.

SUBMITTER: Braunschweig H

PROVIDER: S-EPMC5492900 | biostudies-other | 2015 Jun

REPOSITORIES: biostudies-other

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Generation of 1,2-azaboretidines via reduction of ADC borane adducts.

Braunschweig H H Gackstatter A A Kupfer T T Scheller T T Hupp F F Damme A A Arnold N N Ewing W C WC

Chemical science 20150416 6

Reaction of the acyclic (diamino)carbene (ADC) :C(NiPr2)2 (1) with different dihaloboranes of the type RBX2 (R = Mes, Dur; X = Cl, Br) smoothly afforded a novel class of ADC-stabilized borane adducts. For MesBBr2 however, the reaction did not stop at the adduct level, but an uncommon rearrangement process occurred, which eventually resulted in the formation of a 5-membered boracycle after elimination of mesitylene. Chemical reduction of the ADC ...[more]

PMID: 28706706

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