170098-98-3

Step 1: Nitration reaction Suspend 2.21 g (16.7 mmol) of nitronium tetrafluoroborate in 30 mL of dichloromethane. Under reflux conditions, 3.0 g (15.9 mmol) of 2-bromo-5-fluorotoluene dissolved in 30 mL of dichloromethane was slowly added dropwise. After the dropwise addition was completed, the reaction mixture was continued to be stirred under reflux conditions for 6 hours. Upon completion of the reaction, the mixture was poured into ice water and extracted with dichloromethane. The organic phases were combined, washed with water, dried over anhydrous sodium sulfate and subsequently concentrated on a rotary evaporator to give a yellow oil. The oil was allowed to stand overnight and the oil crystallized. The crystals were collected by filtration, washed with 2 mL of pentane and dried to give 265 mg (6.9% yield) of the target product 1-bromo-4-fluoro-2-methyl-5-nitrobenzene. The product was analyzed by GC/MS (Method 8, EIpos): retention time Rt = 4.49 min, mass-to-charge ratio m/z = 232/234 [M]+.

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