Reaction #1482

Reaction equation

ethylene glycol

3,4-dihydro-4,4-dimethyl-7-acetyl-naphthalen-1(2H)-one

p-toluenesulfonic acid monohydrate

3,4-dihydro-4,4-dimethyl-6-acetyl-naphthalen-1(2H)-one

→

title compound

6-(2-methyl-1,3-dioxolan-2-yl)-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one

Solvents

benzene

Conditions

Workup

1. 1
   TemperatureThe resulting solution was heated
2. 2
   Temperatureto reflux for 18 h
3. 3
   Concentrationconcentrated under reduced pressure

Procedure

A solution of 1.80 g (8.34 mmol) of a 1:5 mixture of 3,4-dihydro-4,4-dimethyl-7-acetyl-naphthalen-1(2H)-one (Compound D14a); and 3,4-dihydro-4,4-dimethyl-6-acetyl-naphthalen-1(2H)-one (Compound D14b) in 50 mL benzene was combined with 517.7 mg (8.34 mmol) of ethylene glycol and 20.0 mg (0.11 mmol) of p-toluenesulfonic acid monohydrate. The resulting solution was heated to reflux for 18 h, cooled to room temperature, and concentrated under reduced pressure. The title compound was isolated by column chromatography (10% EtOAc-hexanes) as a colorless oil.

Source