[CH3:1][O:2][C:3](=[O:12])[CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[C:7]([OH:11])[CH:6]=1.I[CH:14]([CH2:16][CH3:17])[CH3:15].C(=O)([O-])[O-].[K+].[K+]>CC(C)=O>[CH3:1][O:2][C:3](=[O:12])[CH2:4][C:5]1[CH:10]=[CH:9][CH:8]=[C:7]([O:11][CH:14]([CH2:16][CH3:17])[CH3:15])[CH:6]=1To 3-hydroxyphenyl acetic acid methyl ester (27.3 g, 165 mmol) in acetone (200 mL) was added 2-iodobutane (55 mL, 478 mmol) and potassium carbonate (83 g, 601 mmol). The mixture was heated at 65° C. for 48 hrs and filtered through a Celite® pad. The filtrate was concentrated in vacuo and the residue was diluted with dichloromethane and water. The aqueous phase was extracted with dichloromethane (3×100 mL). The combined extracts were washed with saturated sodium chloride (50 mL), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo to afford (3-sec-butoxy-phenyl)-acetic acid methyl ester. To a solution of (3-sec-butoxy-phenyl)-acetic acid methyl ester in methanol (200 mL) was added 10N sodium hydroxide solution (50 mL). The reaction mixture was stirred at 60° C. for 4 hrs. The solvent was evaporated and the mixture was acidified to pH=3 by addition of 6N hydrogen chloride solution. The aqueous phase was extracted with dichloromethane (3×100 m]L). The combined extracts were washed with saturated aqueous sodium chloride solution (80 mL), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo to afford (3-sec-butoxy-phenyl) acetic acid (25 g, 73% yield) as a light brown oil.
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