[Cl-].[Al+3].[Cl-].[Cl-].[Cl:5][C:6]1[CH:14]=[CH:13][CH:12]=[C:11]([Cl:15])[C:7]=1[C:8](Cl)=[O:9].[CH3:16][O:17][C:18]1[CH:19]=[C:20]([CH3:28])[CH:21]=[C:22]([O:26]C)[C:23]=1[O:24][CH3:25]>ClCCl>[Cl:5][C:6]1[CH:14]=[CH:13][CH:12]=[C:11]([Cl:15])[C:7]=1[C:8]([C:21]1[C:20]([CH3:28])=[CH:19][C:18]([O:17][CH3:16])=[C:23]([O:24][CH3:25])[C:22]=1[OH:26])=[O:9]Aluminum chloride (14.67 g, 0.1 mol), 2,6-dichlorobenzoyl chloride (20.95 g, 0.1 mol) and a solution of 3,4,5-trimethoxytoluene (18.22 g, 0.1 mol) in dichloromethane (50 ml), are slowly and consecutively added to dichloromethane stirred at 0° C., stirred for 1 h at ice bath temperatures and for 16 h at room temperature, and poured into ice. The organic layer is separated, washed with dilute hydrochloric acid and water, dried, and, after addition of silica gel (100 g), concentrated in vacuo. A flash chromatography column is packed with silica gel (400 g) andthe charged silica gel is layered on top of that. Elution with petrol ether/ethyl acetate (90/10, 1 l; 80/20, 1 l; 50/50, 1 l) yields 2,6-dichloro-3',4'-dimethoxy-2'-hydroxy-6'-methylbenzophenone, 10.35 g, (30% y), mp. 161° C.
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