1-(3,5-dimethylphenyl)-1H,4H,5H-pyrazolo[3,4-d]pyrimidin-4-one → 4-chloro-1-(3,5-dimethylphenyl)-1H-pyrazolo[3,4-d]pyrimidine

Participants

Reaction Conditions

Reaction Steps

650.0 g of Phosphorus (V) oxychloride (POCl3) was charged into a 2.0 L 4 necked round bottom flask connected to a mechanical stirrer, thermo meter socket, and condenser under nitrogen atmosphere. 60.0 g (0.25 mol) of 1-(3,5-Dimethyl-phenyl)-1,5-dihydro-pyrazolo[3,4-d]pyrimidine-4-one (Compound No. 78) was charged. Reaction mass temperature was raised to reflux (105-108° C.). Maintained the mass temperature at reflux for 8-9 hour's. Reaction mass temperature was cooled to 25-30° C. and 600.0 ml of chloroform was charged. Maintained the mass temperature at 25-30° C. for 30-45 min. 2.0 kg's of crushed ice was charged into a 5.0 L 4 necked round bottom flask connect to a mechanical stirrer, thermo meter socket, and condenser. Reaction mass was added slowly at maintaining the mass temperature below 10° C. Maintained the mass temperature at 0-10° C. for 30-45 min. Mass temperature was raised to 25-30° C. 600.0 ml of Chloroform was charged. Maintained the mass temperature at 25-30° C. for 30-45 min and settled the mass for 20-30 min. Separated the bottom organic layer. Organic layer was dried with sodium sulphate upto obtaining the moisture content is not more than 0.20% w/v. 15.0 g of carbon was charged. Mass temperature was raised to 45-50° C. Maintained the mass temperature at 45-50° C. for 30-45 min. Carbon and sodium sulphate was filtered through hyflow bed and bed was washed with 300.0 ml of chloroform. Filtrate was collected into a flask. Chloroform was distilled completely under vacuum at mass temperature not crossing 60° C. Finally applied high vacuum to complete remove the traces of chloroform at mass temperature not crossing 60° C. Mass temperature was cooled to 25-30° C. and release the vacuum. 250.0 ml of isopropyl ether was charged. Maintained the mass temperature at 25-30° C. for 45-60 min. Solid was filtered and the solid was washed with 50.0 ml of isopropyl ether. Compound was dried under vacuum at 55-60° C. Dry weight of the compound: 56.0 g (yield 86.6%).

Provenance & Evidence