GENERAL STEPS: Potassium hydroxide (0.35 g, 6.17 mmol) was added to a solution of 4-amino-phthalimide (1.00 g, 6.17 mmol) in dimethylformamide (30 mL) and the reaction mixture was stirred at room temperature for 2 hours. Subsequently, iodomethane (0.88 g, 6.17 mmol) was added and stirring was continued at the same temperature for 18 hours. Upon completion of the reaction, water (50 mL) and ethyl acetate (50 mL) were added for extraction and the organic phase was separated. The organic phase was washed sequentially with saturated saline, dried with anhydrous sodium sulfate and concentrated under reduced pressure to remove the solvent. The crude product was purified by silica gel column chromatography (elution gradient: 0-100% cyclohexane solution of ethyl acetate) to afford N-methyl-4-amino phthalimide as a yellow solid (1.00 g, 92% yield). The product was characterized as follows: 1H NMR (DMSO-d6) δ 7.46 (d, J = 8.24 Hz, 1H), 6.90 (d, J = 2.00 Hz, 1H), 6.77 (dd, J = 8.24, 2.00 Hz, 1H), 6.42 (br.s, 2H), 2.94 (s, 3H); 13C NMR (DMSO-d6) δ 168.87, 168.57, 155.27, 135.10, 125.17, 117.33, 116.84, 107.42, 23.83; MS (m/z): 177 [M + H]+.
