Water → 3-[(4-Chlorophenyl)methyl]-6,6-dimethylcyclohex-2-en-1-one

Participants

Reaction Steps

A solution of the 1-(4-chlorobenzyl)-4,4-dimethylcyclohex-2-en-1-ol (368 g, 1.47 mol) obtained in (a) in 40/60 petroleum (40 ml) was added in a steady stream to a solution of sodium dichromate (217 g, 0.74 mol) in dilute sulphuric acid (250 g, 2.6 mol 98% sulphuric acid in 1.5 liters of water). The reaction mixture was then held at a temperature between 10° and 30° C. and stirred for 40 minutes. Water (500 ml) and diethyl ether (700 ml) were added and the aqueous layer extracted twice with diethyl ether (2×700 ml). The organic phases were then combined and backwashed with saturated sodium bicarbonate solution (1×500 ml) and water (1×500 ml). The solvent was then flashed off to give 349 g crude 1-(4-chlorobenzyl)-4,4-dimethylcyclohex-1-en-3-one as a beige coloured granular solid. Trituration in petrol gave a pure sample of the desired product, m.pt. 87°-90° C.

Provenance & Evidence