ADDITION AND SUBSTITUTION-REACTIONS AT TETRAFLUORODIBORANE AND TETRACHLORODIBORANE(4)

From equimolar mixtures of B2F4 and Me(n)N(SiMe3)3-n (n = 0-3) the mono-addition products 1-4 are formed at low temperatures. By elimination of Me3SiF the adduct 2 gives the dimeric monosubstituted diborane 8, which slowly decomposes at room temperature to the aminoborane 6 and (BF)n. The course of the reactions was studied by means of B-11 and F-19 NMR spectroscopy and by measuring the vapor pressures. According to the B-11 and P-31 NMR spectra the reaction of B2Cl4 with PCl5 or [Me4N]Cl in liquid hydrogen chloride at 0-degrees-C does not yield [PCl4]2+[B2Cl6]2- or [Me4N]2+[B2Cl6]2- but gives [PCl4]+[BCl4]-, PCl3 and BCl3 or [Me4N]+[BCl4]- and BCl3 besides (BCl)n.