Hydrochloric Acid → Propofol

Participants

Reaction Conditions

Reaction Steps

To the solution of 4-hydroxy-3,5-diisopropyl benzoic acid 100 g (0.45 M) (example 1) in ethylene glycol (150 ml) was added sodium hydroxide pallets 41.5 g (1.03M) and heated to 140-145° C. under inert atmosphere. After 7 hrs of continued heating at 140-145° C., the reaction mass was cooled to room temperature and diluted with 5 times water. The pH of the mass was then adjusted to 1-2 using concentrated Hydrochloric acid, reaction mixture was stirred for one hour and extracted three times with 200 ml toluene, combined toluene layers were washed twice with 5% aq. sodium bicarbonate solution (50 ml) and finally with water (200 ml), solvent was removed under reduced pressure and a dark brown colored residue which remained was distilled under high vacuum condition (0.2 mm/Hg) to yield 75 g (93.5%) of 2,6-diisopropyl phenol collected as a colourless to pale yellow oily liquid, HPLC Purity 99.93%.

Provenance & Evidence