A mixture of 2-(2-(2-oxo-1,2-dihydropyridin-4-yl)ethyl)isoindoline-1,3-dione (300 mg, 1.1 mmol) CH3I (1.0 g, 7 mmol) and K2CO3 (700 mg, 5 mmol) in 30 mL of DCM and 10 mL of DMF was stirred at room temperature for 3 days. 30 mL of DCM was added. The mixture was washed with H2O (3×30 mL), dried over anhydrous sodium sulfate, concentrated under reduce pressure to give 2-(2-(1-methyl-2-oxo-1,2-dihydropyridin-4-yl)ethyl)isoindoline-1,3-dione (230 mg, 73%) as a white solid. LC-MS: 283 [M+H]+, tR=1.29 min.
