Reaction #6702

Reaction equation

water

4-Bromobenzaldehyde

p-toluenesulfonic acid monohydrate

ethylene glycol

→

2-(4-bromophenyl)-1,3-dioxolane

Solvents

ethyl acetate

benzene

Conditions

Workup

1. 1
   WashThis solution was washed twice with aqueous bicarbonate
2. 2
   Dryingdried over magnesium sulfate
3. 3
   Concentrationconcentrated under reduced pressure
4. 4
   OtherA colorless oil was recovered

Procedure

4-Bromobenzaldehyde (3 g, 0.0162 mol) in benzene (60 mL) was treated with p-toluenesulfonic acid monohydrate (0.15 g, 0.79 mmol) and ethylene glycol (5 mL, 0.0896 mol). The reaction was refluxed under nitrogen with azeotropic removal of water. After 3 hours, the reaction was cooled to room temperature and diluted with an equal volume of ethyl acetate. This solution was washed twice with aqueous bicarbonate, dried over magnesium sulfate and concentrated under reduced pressure. A colorless oil was recovered. Yield=2.83 g (92%). TLC (5% ethyl acetate in hexanes) showed clean product, Rf=0.17.

Source