Example 22 Preparation of 1-(4-methyl-2-nitrophenyl)ethan-1-one (C84): In a reaction flask was added 4-methyl-2-nitro-1-(prop-1-en-2-yl)benzene (11.4 g, 64.3 mmol), dichloromethane (292 mL) and methanol (29.2 mL). The reaction mixture was cooled to -78° C. Ozone was passed into the reaction mixture and stirred at -78° C for 3 hours. Subsequently, the reaction mixture was purged with nitrogen to remove unreacted ozone. Dimethyl sulfide (14.0 mL, 189 mmol) was added, and the reaction mixture was stirred and gradually warmed to room temperature overnight. Upon completion of the reaction, the mixture was concentrated. Purification by fast column chromatography using ethyl acetate/hexane as eluent afforded the target product 1-(4-methyl-2-nitrophenyl)ethanone as an oil (8.90 g, 70% yield).1H NMR (300 MHz, CDCl3) δ 7.85 (dd, J = 1.7, 0.8 Hz, 1H), 7.50 (ddd, J = 7.8, 1.7, 0.8 Hz), 7.50 (ddd, J = 7.8, 0.8 Hz). 1.7, 0.8 Hz, 1H), 7.35 (dd, J = 7.7, 0.9 Hz, 1H), 2.53 (s, 3H), 2.48 (s, 3H).
