Carbon tetrabromide → 3,4-Dimethoxyphenethyl bromide

Participants

Reaction Steps

Part A. A solution of 3,4-dimethoxyphenethyl alcohol (7.30 g, 40.1 mmol) and carbon tetrabromide (17.3 g, 52.1 mmol) in methylene chloride (100 mL)was cooled to 0° C., and a solution of triphenylphosphine (13.7 g, 52.1 mmol) in methylene chloride (50 mL) was added dropwise with stirring.After 20 hours, the reaction mixture was evaporated, and separated by flashchromatography (1:9 ethyl acetate-hexane) to afford the product, 1-(2-bromoethyl)-3,4-dimethoxybenzene, as a waxy solid, mp 72°-73° C. (9.48 g, 38.7 mmol, 96%). 1H NMR (CDCl3): δ 6.82 (1H, d, J=8.1 Hz); 6.75 (1H, dd, J=8.1, 1.8 Hz); 6.73 (1H, d, J=1.8 Hz); 3.88 (3H, s); 3.87 (3H, s); 3.55 (2H, t, J=7.7 Hz); 3.11 (2H, t, J=7.7 Hz). Mass spectrum (NH3 -CI/DDIP): m/z 264 (93%); 262 (100%); 245 (9%); 165 (6%).

Provenance & Evidence