Hydrochloric Acid → HCID 178428979, compound

Participants

Reaction Conditions

Reaction Steps

7-Chloro-4-hydroxy-2-(4-methoxy-2-methylphenyl)-1,2,5,10-tetrahydropyridazino[4,5-b]quinoline-1,10-dione (1.00 g, 2.61 mM) was stirred in methanesulfonic acid (10 mL) to give a brown solution. This solution was heated to 150° C. for 3 hours and cooled to room temperature. The cooled solution was added dropwise to water (50 mL) with stirring to give a grey suspension which was stirred for 20 hours and filtered. The collected solids were washed with water and then suspended in water (50 mL). To this suspension was added choline hydroxide solution (2 mL, 45 wt % in methanol) which dissolved the solids to give a brown solution. This solution was heated to reflux for 1 hour, additional choline hydroxide solution (2 mL) was added and the solution was heated to reflux for 3 hours. The solution was cooled to room temperature and acidified to pH=1 with 1N HCl to give a brown suspension. The suspension was filtered and the collected solids were washed with water to give a brown solid. Several recrystallizations from hot methanol gave the title compound as an off-white powder (0.35 g, 36%), mp 287° C. (decomp.); MS(CI): 370.

Provenance & Evidence