[OH:1][C:2]1[C:3]([CH3:18])=[C:4]([CH3:17])[C:5]2[O:10][C:9]([CH3:14])([C:11]([OH:13])=[O:12])[CH2:8][CH2:7][C:6]=2[C:15]=1[CH3:16].[CH3:19][O:20][CH2:21]Br.C(O)(=O)C>N1C=CC=CC=1>[CH3:19][O:20][CH2:21][O:1][C:2]1[C:3]([CH3:18])=[C:4]([CH3:17])[C:5]2[O:10][C:9]([CH3:14])([C:11]([OH:13])=[O:12])[CH2:8][CH2:7][C:6]=2[C:15]=1[CH3:16]50 grams (0.2 mol) of 6-hydroxy-3,4-dihydro-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carboxylic acid are dissolved in 150 cm3 of anhydrous pyridine. 16.34 cm3 (0.2 mol) of bromomethyl methyl ether are added dropwise. The mixture is stirred for 2 hours and then the solution is poured onto ice. The mixture is acidified with acetic acid and then extracted with methylene chloride. The organic phase is washed with water and dried over anhydrous sodium sulfate, then the title product is purified by passing through a column of silica gel, eluting with methylene chloride.
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