反应详情

温度

95 °C

A suspension of 5-amino-1H-pyrazole-4-carboxylic acid (271 mg, 2.1 mmol) and 1,1,3,3-tetraethoxy-2-methyl-propane (prepared accordingly to the procedure described in JACS126(7), 2004, 2194) (0.5 g, 2.1 mmol) in an aqueous solution of hydrochloric acid (6 M, 1.3 mL) was heated at 95° C. in a sealed tube. The solid material completely dissolved when the temperature reached 82° C. and then a solid precipitate crushed out of solution, stirring was continued for 5 minutes. The resulting mixture was cooled to room temperature and the solid was collected by filtration, rinsed with water and dried in vacuum oven to afford 305.1 mg (81% yield) of 6-methyl-pyrazolo[1,5-a]pyrimidine-3-carboxylic acid.

1. customprepared accordingly to the procedure
2. dissolutionThe solid material completely dissolved when the temperature
3. customreached 82° C.
4. customa solid precipitate crushed out of solution
5. temperatureThe resulting mixture was cooled to room temperature
6. filtrationthe solid was collected by filtration
7. washrinsed with water
8. customdried in vacuum oven