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A mixture of 2-methyl-5-nitrobenzoic acid (10.0 g, 55.2 mmol) in ethanol (200 ml) was cooled to 0° C. with an ice bath and thionyl chloride (16.0 mL, 220 mmol) was added dropwise over 10 min. After this time, the mixture was warmed to room temperature for 1 h, then transferred to an oil bath and heated to reflux overnight. The mixture was then cooled to room temperature and concentrated under reduced pressure. Purification by flash chromatography (silica, 9:1 hexanes/ethyl acetate) afforded ethyl 2-methyl-5-nitrobenzoate (12.4 g, quant.) as a pale yellow oil: 1H NMR (300 MHz, CDCl3) δ 8.76 (d, J=2.5 Hz, 1H), 8.24 (dd, J=8.5, 2.5 Hz, 1H), 7.43 (d, J=8.4 Hz, 1H), 4.42 (q, J=7.2 Hz, 2H), 2.72 (s, 3H), 1.44 (t, J=7.1 Hz, 3H).

1. temperatureAfter this time, the mixture was warmed to room temperature for 1 h
2. customtransferred to an oil bath
3. temperatureheated
4. temperatureto reflux overnight
5. temperatureThe mixture was then cooled to room temperature
6. concentrationconcentrated under reduced pressure
7. customPurification by flash chromatography (silica, 9:1 hexanes/ethyl acetate)