Ammonia → 6-Chloro-3-methyl-5-nitroisoquinoline

Participants

Reaction Steps

To a solution of 6-chloro-3-methylisoquinoline (10.0 g, 57.5 mmol) in concentrated H2SO4 (100 mL) was added dropwise during 10 min. a solution of KNO3 (6.05 g, 60 mmol) in concentrated H2SO4 (50 mL) at 5° C. Care was taken that the temperature of the reaction mixture did not rise above 10° C. The reaction mixture was stirred for 3 h at room temperature, poured onto ice (200 g) and rendered basic (pH=10) with a 33% aqueous ammonia solution. A dark yellow precipitate was formed, which was filtered off, thoroughly rinsed with water and taken up in dichloromethane. The organic phase was washed with water and brine, dried over Na2SO4, filtered and dried in vacuo to afford a pale brown solid. Re-crystallization from dichloromethane/pentane afforded the title compound as pale brown crystals (9.2, 41.4 mmol, 72%). MS (ES+): 223 (M(C10H735ClN2O2)+H)+.

Provenance & Evidence