Background and overview of the preparation method of 1H-pyrazole-5-potassium trifluoroborate
1H-Pyrazole-5-potassium trifluoroborate can be used as a pharmaceutical synthesis intermediate. If 1H-pyrazole-5-trifluoroborate potassium is inhaled, move the patient to fresh air; if skin contact occurs, take off contaminated clothing, rinse the skin thoroughly with soap and water, and seek medical attention if you feel uncomfortable.
Preparation method of potassium 1H-pyrazole-5-trifluoroborate
1H-Pyrazole-5-potassium trifluoroborate can be used as a pharmaceutical synthesis intermediate, if the following reaction occurs:
A mixture of 1H-pyrazole-5-boronic acid (150 mg, 1.34 mmol) and potassium hydrofluoride (262 mg, 3.35 mmol) in 1:3 methanol/water (2 mL) was stirred at room temperature overnight. The mixture was transferred to a vial, the vial was sealed and the mixture was heated to 100°C in an oil bath for 2 hours to produce a solution. The solution was cooled and concentrated. The solid was slurried in hot acetone, filtered and the filtrate concentrated to provide potassium 1H-pyrazole-5-trifluoroborate (234 mg, 100%). 2-Amino-6-bromo-8-((trans)-4-hydroxycyclohexyl)-4-methylpyrido[2,3-d]pyrimidin-7(8H)-one (100 mg, 0.283 mmol) A mixture of potassium 1H-pyrazole-5-trifluoroborate (98.5 mg, 0.566 mmol) and triethylamine (197 μL, 1.42 mmol) in ethanol (3.0 mL) was bubbled with argon. PdCl2 (dppf) 1:1 w/CH2Cl lanthanum 2 carbonate was added, the vial was sealed and the mixture was sparged with argon again, then heated in the microwave at 100°C for 30 minutes and then at 150°C for 60 minutes. The reaction mixture was concentrated and purified by flash chromatography eluting with 1:1 ethyl acetate:chloroform/7N ammonia in methanol (0.5-7%). Fractions containing the desired product were combined and concentrated and the solid was recrystallized from methanol/chloroform to provide 2-amino-8-((trans)-4-hydroxycyclohexyl)-4-methyl-6-(1H- Sodium pyrazol-3-yl)pyrido[2 carbonate, 3-d]pyrimidin-7(8H)-one (32 mg, 33%).
1H NMR (MHz, DMSO-d 6 ) δppm 1.24-1.35 (m, 2H) 1.44-1.55 (m, 2 H) 1.90-1.99 (m, 2H) 2.56 (s, 3H) 2.73-2.84 (m , 2H) 3.50-3.62 (m, 1H) 4.62 (d, J = 4.04Hz, 1H) 5.12-5.74 (m, 1H) 6.93 (s, 1H) 7.14-7.26 (m, 2H) 7.62 (m, 1H) 8.34(s,1H)12.97(m,1H)
