in dichloromethane N2 atmosphere, addn. of soln. of stannyl compound to soln. of borane at -78°C, slow warming to room temp., stirring (25°C, 12 h); removement of solvent (25°C, 12 Torr), removement of Me3SnBr by fractional distillation (30°C, 1E-2 Torr or 53-55°C, 12 Torr); elem. anal.;

in dichloromethane under N2, BBr3 in CH2Cl2 added dropwise to a soln. of Sn-compound at -78°C, warmed to room temp.; CH2Cl2 removed at room temp. and 100 Torr, distilled at 26°C and 1E-1 Torr (Me3SnBr), distilled at 146°C and 1E-3 Torr; elem. anal.;