C([O:8][C:9]1[CH:18]=[C:17]([O:19]CC2C=CC=CC=2)[C:16]([C:27]([CH3:29])=[CH2:28])=[CH:15][C:10]=1[C:11]([O:13][CH3:14])=[O:12])C1C=CC=CC=1.CO>[Pd].C(O)C>[OH:8][C:9]1[CH:18]=[C:17]([OH:19])[C:16]([CH:27]([CH3:29])[CH3:28])=[CH:15][C:10]=1[C:11]([O:13][CH3:14])=[O:12]10% Palladium on carbon (350 mg) was added to a suspension of methyl 2,4-bis-benzyloxy-5-isopropenylbenzoate [prepared as per WO 2006/109085 A1] (3.88 g, 10.0 mmol) in ethanol (30 ml) and the mixture was stirred at room temperature under a hydrogen atmosphere for 1 hour. Methanol (20 ml) was added to aid dissolution and the mixture was stirred at room temperature under a hydrogen atmosphere for 16 hours. The mixture was filtered, the catalyst was rinsed with methanol (3×20 ml) and the combined filtrates were evaporated in vacuo to afford methyl 2,4-dihydroxy-5-isopropylbenzoate (2.10 g, 100%) as a colourless solid. 1H NMR (DMSO-d6) 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). MS: [M+H]+ 211.
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