The general procedure for the synthesis of methyl 2,4-dihydroxy-5-isopropylbenzoate from methyl 2,4-bis-benzyloxy-5-isopropenylbenzoate was as follows: methyl 2,4-bis-benzyloxy-5-isopropenylbenzoate (3.88 g, 10.0 mmol) was dissolved in ethanol (30 ml) to form a suspension. 10% palladium carbon catalyst (350 mg) was added and the reaction mixture was stirred at room temperature under hydrogen atmosphere. To promote dissolution, additional methanol (20 ml) was added. Stirring was continued at room temperature and under hydrogen atmosphere for 16 hours. Upon completion of the reaction, the mixture was filtered to remove the catalyst and the catalyst was washed with methanol (3 x 20 ml). The filtrates were combined and the solvent was removed by vacuum evaporation to afford methyl 2,4-dihydroxy-5-isopropylbenzoate (2.10 g, 100% yield) as a colorless solid. The product was confirmed by 1H NMR (DMSO-d6): δ 10.54 (1H, s), 10.44 (1H, br s), 7.52 (1H, s), 6.37 (1H, s), 3.85 (3H, s), 3.08 (1H, m), 1.13 (6H, d). Mass spectral analysis showed [M + H]+ 211.
