[CH3:1][C:2]1[CH:3]=[C:4]([OH:9])[CH:5]=[CH:6][C:7]=1[CH3:8].[O-]CC.[Na+].Br[CH2:15][CH2:16][CH2:17][C:18]([O:20]CC)=[O:19].[OH-].[Na+]>C(O)C.O>[CH3:1][C:2]1[CH:3]=[C:4]([CH:5]=[CH:6][C:7]=1[CH3:8])[O:9][CH2:15][CH2:16][CH2:17][C:18]([OH:20])=[O:19]3,4-Dimethylphenol (24.5 g, 0.2 mol) was dissolved in 125 ml of anhydrous ethanol. 75 ml of 21 wt % sodium ethoxide solution in ethanol (0.2 mol) was added to the solution. The mixture was stirred at room temperature for 10 min. Ethyl 4-bromobutyrate (40 g, 0.205 mol) was then added. The reaction mixture was refluxed at 80° C. for 24 h. The precipitate was filtered off. The filtrate was then mixed with a solution of sodium hydroxide (10 g, 0.25 mol) in 150 ml of water. The mixture was stirred at 70° C. for about 2 h, monitored with HPLC. It was diluted with 150 ml of water and acidified to pH 1. Oily precipitate formed immediately. It was collected by decanting the supernatant and washed with water twice (100 ml×2). The oily precipitate solidified after being kept in water at room temperature over night.
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