[CH3:1][C:2]([C:4]1[CH:9]=[CH:8][C:7]([OH:10])=[C:6]([O:11][CH3:12])[CH:5]=1)=[O:3].[CH2:13](Br)[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.C(=O)([O-])[O-].[K+].[K+]>CN(C=O)C.O>[CH3:1][C:2]([C:4]1[CH:9]=[CH:8][C:7]([O:10][CH2:13][C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)=[C:6]([O:11][CH3:12])[CH:5]=1)=[O:3]The starting material, 4-benzyloxy-3-methoxyacetophenone, was obtained by heating a solution of 4-hydroxy-3-methoxyacetophenone (20 g, 0.12 mol), benzyl bromide (15.7 ml, 0.13 mol) and potassium carbonate (49.8 g, 0.36 mol), in DMF (400 ml) at 40° C. overnight. After cooling, the mixture was diluted with water, acidified to approximately pH3 and extracted with ethyl acetate. The organic layer was washed with brine, dried (MgSO4) and the solvent evaporated. The residue was purified by flash chromatography using petroleum ether/ethyl acetate (8/2 followed by 65/35) as eluent to give 4-benzyloxy-3-methoxyacetophenone (30.3 g, 99%).
Loading…
