4-Iodophthalonitrile 97

1.6 g (0.011 mol) 4-aminophthalonitrile was dissolved in 22.4 mL of 2.5 M H2SO4. The mixture was cooled to 0 C. To the solution was slowly added 0.9 g (0.013 mol) of NaNO2 dissolved in 3.5 mL of water. After the mixture was stirred for 30 minutes, 2.08 g (0.013 mol) of KI dissolved in 12.8 mL of water was added. The mixture was further stirred for 45 minutes at room temperature. After this period, the brown solid was filtered and washed with water. It was dissolved in a minimal amount of chloroform. The solution was washed first with saturated Na2S2O3 and then with water. It was dried over Na2SO4. After the solution was filtered, it was dried in vacuum and purified with column chromatography over silica gel by eluting with dichloromethane. Molecular formula: IC6H3-1,2-(CN)2 (254.03 g/mol). Yield: 2.37 g (85%).