p-Toluenesulfonic acid → trans 4-(Bromomethyl)-2-methoxy-1,3-dioxolane

Participants

Reaction Steps

To a solution of 3-bromo-1,2-propanediol (6.0 g, 38.7 mmol) in benzene (90 mL) was added trimethylorthoformate (4.23 mL, 38.7 mmol, 1 eq.) and p-toluenesulfonic acid (pTSA, few crystals). The mixture was stirred for 20 hr at 85°-90° C., then cooled to room temperature and benzene was removed under reduced pressure. The crude material was obtained in 96% yield (7.26 g) as a mixture of cis and trans isomers in a 1:1 ratio.

Provenance & Evidence