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1. Concentrated sulfuric acid (1 mL) was added slowly and dropwise to a solution of 2-amino-4-methylbenzoic acid (1.0 g, 6.62 mmol) in anhydrous methanol (10 mL) at 0 °C. 2. The reaction mixture was heated to reflux for 16 hours. 3. Upon completion of the reaction, the mixture was cooled to room temperature and subsequently concentrated under reduced pressure to remove the solvent. 4. The concentrated crude product was diluted with deionized water (25 mL) and the pH was adjusted to basic with sodium bicarbonate solution (10 mL). 5. The aqueous layer was extracted using ethyl acetate (2 x 50 mL) and the organic phase was collected. 6. The organic phases were combined and washed sequentially with deionized water (50 mL) and saturated saline (50 mL). 7. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford methyl 2-amino-4-methylbenzoate (900 mg, 82% yield) as a yellow liquid.

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