Scheme 5, Step B. To a solution of methyl 3,5-dimethyl-4-nitrobenzoate (10.0 g, 0.0478 mol) in methanol (100 mL) at 0°C was sequentially added iron powder (15.7 g, 0.2869 mol) and 37% hydrochloric acid (1.72 g, 0.0478 mol). The reaction mixture was heated to 80 °C and kept for 16 hours. After completion of the reaction, the mixture was cooled to room temperature, filtered through a Celite TM bed and the filter cake was washed with methanol. The filtrate was concentrated to dryness to afford methyl 4-amino-3,5-dimethylbenzoate as an unpurified solid (7.8 g, 99% yield). Mass spectrum (m/z): 180.2 (M + 1).
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