Dimethyl Sulfate → 1-Methyl-3-(methylsulfinyl)-4(1H)-cinnolinone

Participants

Reaction Steps

Dimethylsulfate [12.5 g (0.1 mole)] was added gradually to a vigorously stirred solution of 6.5 g (0.0298 mole) of 3-(methylsulfinyl)-4(1H)-cinnolinone in 120 ml of 1N sodium hydroxide solution at 30°C. The temperature rose to 40° as the suspended dimethyl sulfate gradually went into solution over a period of 15 minutes. After an additional one-half hour of stirring, potassium carbonate excess was added to salt-out an oil. The product was extracted into 800 ml of methylene chloride, the solution was dried over K2CO3, charcoaled, filtered and concentrated. Wt 6.4 g (96.7%) mp. 187°-189°C. Recrystallization from 2-propanol-petroleum ether gave pure material, mp. 189°-191°C.

Provenance & Evidence