To a suspension of 5-amino-2-isopropyl-6-nitroisoindoline-1,3-dione (0.37 g) in 250 mL of MeOH was added 5 mL of AcOH. The resulting solution was degassed with argon and then charged with 10% Pd/C (0.12 g, 50% wet) and hydrogenated at 40 psi of hydrogen for 16 h. Another 2 mL of AcOH was added to the mixture and then solids were filtered off. The filtrate was cooled to −50° C. and a solution of 4-chloro-2-methoxynicotinaldehyde (0.31 g, 1.78 mmol) in 200 mL of MeOH was added dropwise under inert atmosphere. The resulting solution was allowed to warm up to rt and stirred for 16 h. Solvent was evaporated and the oily residue was purified by column chromatography (7.5% MeOH in dichloromethane) to give title compound as a solid (0.23 g, 29.3%). 1H NMR (500 MHz, CDCl3) δ 8.18 (s, 1H), 8.12 (d, 1H), 8.03 (s, 1H), 7.90 (d, 1H), 6.92 (d, 1H), 6.75 (d, 1H), 5.39 (s, 2H), 4.56 (p, 1H), 3.72 (s, 3H), 3.61 (s, 3H), 1.50 (d, 6H). ESI MS: m/z 371.1 (M+1).
