Potassium Hydroxide → 2,4-Bis(benzyloxy)-5-isopropenylbenzoic acid

Participants

Reaction Conditions

Reaction Steps

Potassium hydroxide (0.527 Kg, 9.4 mol) was added to a stirred suspension of methyl 2,4-bis-benzyloxy-5-isopropenyl-benzoate (3.1 Kg, 8 mol, step 4) in methanol (18.6 L) and water (12.4 L) and the mixture was stirred and held at reflux for 3 hours. The methanol was removed under partial vacuum from the vessel, and to the remaining solution was added toluene (62 L). The solution was heated to 40° C. and to the mixture was added conc HCl (1.36 L). The biphasic mixture is heated to 50° C. and the phases separated. The organic phase was washed with water (31 L) at 50° C. and the organic phase was evaporated under reduced pressure to give 2,4-bis-benzyloxy-5-isopropenyl-benzoic acid 2.851 Kg (95% yield) as a colourless solid.

Provenance & Evidence