4,4,4-Trifluoro-1-(4-trifluoromethylphenyl)-1,3-butanedione → 7-(Trifluoromethyl)-5-(4-(trifluoromethyl)phenyl)pyrazolo[1,5-a]pyrimidine

Participants

Reaction Steps

A mixture of 4,4,4-trifluoro-1-(4-trifluoromethyl-phenyl)-butane-1,3-dione (Example C.1, method 1, step 1) (2.84 g, 10 mmol) and 3-aminopyrazole (0.83 g, 10 mmol) in acetic acid (20 mL) were refluxed for 4 h. The reaction mixture was cooled to rt and poured into ice water (200 mL), extracted with EtOAc, dried over MgSO4, filtered and concentrated, and triturated with toluene, and dried to give 7-trifluoromethyl-5-(4-trifluoromethyl-phenyl)-pyrazolo[1,5-a]pyrimidine (3.28 g, 99%) as a yellow solid. MS (ISP) 332.1 [(M+H)+]; mp 110–111° C.

Provenance & Evidence