Thionyl Chloride → 4-Chloro-6,7-dimethoxyquinazoline

Participants

Reaction Conditions

Reaction Steps

720.0 g (6.05 mol) of thionyl chloride and 50.0 g (0.243 mol) of 6,7-dimethoxy-3H-quinazoline-4-one were charged into a 2.0 L 4 necked round bottom flask connected to a mechanical stirrer, thermometer socket and double surface reflux condenser. Reaction mass temperature was raised to reflux temperature (78-80° C.). 20.0 ml of dimethyl formamide was added slowly at reflux temperature. Maintained the mass temperature at reflux for 7-8 hours under stirring. Distilled off thionyl chloride completely under vacuum at below 70° C. Cooled the mass temperature to 40° C. to 45° C. under nitrogen atmosphere 1000.0 ml of hexane was charged under stirring. Maintained the mass temperature at 40° C. to 45° C. for 30-45 min. Cooled the mass temperature 25-30° C. Maintained the mass temperature at 25-30° C. for 45-60 min under nitrogen atmosphere. Filtered the solid under nitrogen atmosphere. Solid was washed with 250.0 ml of hexane. Compound was dried in vacuum tray drier containing phosphorus pentoxide at 30-35° C. till the loss on drying is not more than 0.50% w/w. Obtained 52.50 g (yield is 96.33% by theory) of yellow coloured product.

Provenance & Evidence