[OH:1][C:2]1[C:11]([CH2:12][CH2:13][CH3:14])=[C:10]2[C:5]([CH2:6][CH2:7][CH:8]([C:15]([O:17][CH3:18])=[O:16])[O:9]2)=[CH:4][CH:3]=1.C(=O)([O-])[O-].[K+].[K+].[CH2:25](Br)[C:26]1[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=1>CN(C)C=O>[CH2:25]([O:1][C:2]1[C:11]([CH2:12][CH2:13][CH3:14])=[C:10]2[C:5]([CH2:6][CH2:7][CH:8]([C:15]([O:17][CH3:18])=[O:16])[O:9]2)=[CH:4][CH:3]=1)[C:26]1[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=1A 250 ml single neck round bottom flask was charged with 5.25 g (21 mmole) of methyl 7-hydroxy-8-n-propylchroman-2-carboxylate, 150 ml of dimethylformamide, 3.59 g (26 mmole) of anhydrous potassium carbonate, and 4.30 g (25 mmole) of benzyl bromide. The flask was stoppered and stirred (magnetic stirrer) at room temperature for 4 hours. The insoluble solids were separated by filtration and the dimethylformamide removed by rotary evaporation. The residue was dissolved in 200 ml ethyl acetate, clarified by filtration, and concentrated to an oily residue by rotary evaporation. The resultant crude material was purified by high pressure liquid chromatography (5% ethyl acetate-hexane), to obtain 5.48 g (77%) of the title compound as a clear oil. Calc: C, 74.09; H, 7.11; Found; C, 74.11; H, 7.06.
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