Donor-acceptor complexation and dehydrogenation chemistry of aminoboranes

Article abstract of DOI:10.1021/ic3018997

A series of formal donor-acceptor adducts of aminoborane (H ₂BNH₂) and its N-substituted analogues (H ₂BNRR′) were prepared: LB-H₂BNRR′₂- BH₃ (LB = DMAP, IPr, IPrCH₂ and PCy₃; R and R′ = H, Me or tBu; IPr = [(HCNDipp)₂C:] and Dipp = 2,6-iPr ₂C₆H₃). To potentially access complexes of molecular boron nitride, LB-BN-LA (LA = Lewis acid), preliminary dehydrogenation chemistry involving the parent aminoborane adducts LB-H₂BNH ₂-BH₃ was investigated using [Rh(COD)Cl]₂, CuBr, and NiBr₂ as dehydrogenation catalysts. In place of isolating the intended dehydrogenated BN donor-acceptor complexes, the formation of borazine was noted as a major product. Attempts to prepare the fluoroarylborane-capped aminoborane complexes, LB-H₂BNH ₂-B(C₆F₅)₃, are also described.