To a stirred mixture of 3.57 g (0.010 mol) of bis(isopropylthio)lead2 in 20 mL of
pentane under argon at 25 °C is added a solution of 0.95 mL (0.010 mol) of Boron Tribromide in 10 mL of
pentane. After the mixture is stirred for 20 min, 10 mL of CH2Cl2 is added and the mixture is heated under
reflux for 2.5 h. The reaction mixture is cooled to 25 °C and the white precipitate (PbBr2) is removed by
filtration under argon. The filtrate is distilled under argon to remove solvents and then distilled under
reduced pressure: 2.13 g Bromobis(isopropylthio)borane (90% yield) of a yellow oil; bp 75-80 °C/2 mmHg.
