Ethylene Glycol → 2-(3-Bromophenyl)-2-methyl-1,3-dioxolane

Participants

Reaction Steps

1-(3-bromophenyl)ethanone (60.6 g), ethylene glycol (83.7 mL), and p-toluenesulfonic acid (0.15 g) were dissolved in benzene (250 mL) and heated at reflux overnight in a Dean-Stark apparatus. The mixture was cooled and washed with water. The aqueous layer was further extracted twice with chlorobutane and the combined organic layers were dried (MgSO4), filtered and the solvent was removed under reduced pressure to yield 75.0 g of a yellow oil. The oil was purified by distillation under reduced pressure (19-24 Pa, 64-74° C.) to afford 70.1 g of the title compound of Step A as an oil. 1H NMR (CDCl3): δ 7.64 (s,1H), 7.40 (m,2H), 7.20 (m,1H), 4.0 (m,2H), 3.7 (m,2H), 1.63 (s,3H).

Provenance & Evidence