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-literature | 2015 Jun

REPOSITORIES: biostudies-literature