反应详情

The free acid was prepared from pemirolast potassium (15.8 g; Chemtronica AB) by dissolution in a mixture of water (100 mL) and THF (80 mL) at room temperature and acidification with acetic acid (1 eq.; 17.5 g; 20% aq.). Firstly, ca. 1 mL of acetic acid was added and the obtained thin slurry was equilibrated for about 30 minutes. Thereafter the rest of the acetic acid was added slowly. The resultant thick slurry was diluted with water (50 mL) and equilibrated for 2 hours and then filtered and washed with water. The resultant solid was dried at 40° C. and under reduced pressure for 5-10 hours to yield 7.5 g of sub-title compound.

1. waitequilibrated for 2 hours
2. filtrationfiltered
3. washwashed with water
4. customThe resultant solid was dried at 40° C. and under reduced pressure for 5-10 hours