[Br:1][C:2]1[CH:3]=[C:4]([CH:11]=[CH:12][C:13]=1[Cl:14])[C:5](N(OC)C)=[O:6].[CH3:15][Mg]Br>C1COCC1>[Br:1][C:2]1[CH:3]=[C:4]([C:5](=[O:6])[CH3:15])[CH:11]=[CH:12][C:13]=1[Cl:14]A solution of 3-bromo-4-chloro-N-methoxy-N-methylbenzamide 105 (2.04 g, 7.3 mmol), was dissolved in 30 mL of dry THF. The solution was chilled to −5° C. in a salt bath under N2. Via syringe, methylmagnesium bromide (2.7 mL, 8.1 mmol) was added slowly to the solution. The solution was stirred for 2 h at −5° C., and then it was warmed to room temperature where it was stirred for another 1 h. The reaction was quenched with saturated NH4Cl, and it was diluted with ether and water. The organic solution was extracted with water and brine. The organic phase was dried over MgSO4, filtered, and concentrated in vacuo. The crude material was then filtered through a bed of silica and the filtrate was concentrated to give 1-(3-bromo-4-chlorophenyl)ethanone 106 (1.55 g, 91% yield) as a white solid.
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