Unsaturated vicinal frustrated phosphane/borane Lewis pairs as ligands in gold(i) chemistry

Abstract

The P/B FLP 6, formed by the 1,1-hydroboration of dimesitylphosphino(trimethylsilyl)acetylene with HB(C₆F₅)₂ forms the Au(I)X complexes 9a (X: Cl) and 10a (X: NTf₂), respectively. Both show marked Au⋯B interactions. The P/B FLP isomer 8, featuring the bulky SiMe₃ substituent at the carbon adjacent to boron forms gold complexes 9b and 10b, both of which show weaker Au⋯B interactions. Complex 10a was employed in the catalytic hydroamination of a series of alkynes with p-toluidine. Complexes 9 and 10 were characterized by X-ray diffraction.