p-Toluenesulfonic acid → 3-Cyclopentene-1-acetic acid, 2,2,3-trimethyl-, ethyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of α-campholenic acid (100 g) and p-toluene-sulfonic acid (2 g) in ethanol (3 liters) was kept at reflux (78° C.) for 3 hours. The alcohol was then removed, the residue taken up in CH2Cl2 (1.5 liters) and the solution extracted with ice cold 5% aqueous sodium hydroxide (2×500 ml) and water (500 ml). Concentration of the CH2Cl2 solution gave a crude product (81 g) which was distilled through a 9" glass packed column to give 75 g of a colorless liquid; bp 90° C. @ 4,8 mm Hg; analysis: 97% (CW 20M fused silica column, 120° C.) ethyl α-campholenate.

Provenance & Evidence