The synthesis steps of 2-Bromo-1,1-dimethoxypropane are as follows. A solution of propanal (125 mL, 170 mmol) m MeOH (85 mL) is stirred at rt, and molecular sieves (3A, powdered, 43 g) are added. The mixture is heated at reflux, Br2 (88 mL, 170 mmol) is added dropwise over 30 mm, and reflux is then continued for 4 5 h. The mixture is stirred overnight at rt, K2CO3 (119 g, 86 mmol) is added, and the resulting slurry is stirred for 25 h. The mixture is filtered, the solid is washed with MeOH (20 mL) added to the filtrate, and the mixture is extracted with pentane (3 x 75 mL). The extracts are d?ed over MgSO4 and evaporated under reduced pressure to afford a pale yellow oil (16 0 g), which is not purified further.