N,N-Diethylaniline → 3-Bromo-4-chloro-1H-pyrazolo[3,4-d]pyrimidine

Temperature

106 °C

3-bromo-1H-pyrazolo[3,4-d]pyrimidin-4-ol (Intermediate A) (15.08 g, 70.5 mmol) was suspended in 189 ml of phosphous oxychloride. Diethylaniline (19 ml, 119.4 mmol) was added and the resulting reaction mixture was heated to 106° C. for 2 hours. After cooling to room temperature, the solvent was removed and the resulting amber syrup was poured to 300 ml of ice-water. 20 minutes later, the aqueous layer was extracted with diethyl ether (500 ml×4). The combined organic layer was washed, dried and evaporated to give 6.87 g of 3-bromo-4-chloro-1H-pyrazolo[3,4-d]pyrimidine as light yellow solid. 1H NMR (DMSO) 8.857 (s, 1H), 14.84 (bs, 1H); LC/MS (MH+=233).

1. customthe resulting reaction mixture
2. temperatureAfter cooling to room temperature
3. customthe solvent was removed
4. additionthe resulting amber syrup was poured to 300 ml of ice-water
5. extraction20 minutes later, the aqueous layer was extracted with diethyl ether (500 ml×4)
6. washThe combined organic layer was washed
7. customdried
8. customevaporated

ORD record

ord-af5b8cd11a6e48ddbdeaaa64cecd13df

Source dataset

uspto-grants-2003_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06660744B1