C([O:4][C:5]([CH3:7])=[CH2:6])(=O)C.N(OC(C)(C)C)=O.[Cl:15][C:16]1[CH:22]=[C:21]([Cl:23])[CH:20]=[C:19]([Cl:24])[C:17]=1N>CC(C)=O.C(OCC)(=O)C>[Cl:15][C:16]1[CH:22]=[C:21]([Cl:23])[CH:20]=[C:19]([Cl:24])[C:17]=1[CH2:4][C:5](=[O:6])[CH3:7]In a 1.5 l sulfonation flask equipped with mechanical stirring, cooling funnel, dropping funnel and thermometer under nitrogen at ambient temperature filled with acetone (240 ml), were added isopropenyl acetate (66 ml, 0.60 mol), tert-butyl nitrite (40 ml, 0.30 mol) and cupric sulfate pentahydrate (2.5 g, 0.001 mol). The resulting light green-blue suspension is stirred for 15 min at ambient temperature. A solution of 2,4,6-trichloroaniline (40 g, 0.20 mol), dissolved in acetone (320 ml) was added dropwise over a period of 2 hours. During the addition, bubbling observed, temperature rose to 30° C. and the mixture turned green. 1 Hour after the addition, an amber solution was obtained. The mixture was stirred for 6 hours. Completion of the reaction was confirmed by GC-MS. The crude mixture was concentrated under reduce pressure to remove most of the acetone and the residue was dissolved in ethyl acetate (300 ml) and wash with 1M hydrochloric acid (2×300 ml), water (2×300 ml) potassium carbonate solution (300 ml) followed by water (300 ml). Combined basic aqueous were re-extracted with of ethyl acetate (150 ml). Combined organics were dried over sodium sulfate, and the organics were concentrated under reduced pressure to give crude 1-(2,4,6-trichloro-phenyl)-propan-2-one (53 g) as a dark brown oil. The crude was dissolved again in ethyl acetate (200 ml) and washed with 1M sodium hydroxide (300 ml) 1M hydrochloric acid (100 ml) and water (200 ml). The organic layers were dried and evaporated to give crude 1-(2,4,6-trichloro-phenyl)-propan-2-one 49 g dark brown oil which crystallized.
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