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

Participants

Reaction Steps

A stirred mixture of commercially available 3-amino-4-bromo-pyrazole (14.00 g, 86.4 mmol) and 4,4,4-trifluoro-1-(4-trifluoromethyl-phenyl)-butane-1,3-dione (Example C.1 step 1) (24.56 g, 86.4 mmol) in acetic acid (170 mL) was heated under reflux conditions for 2.5 h. The reaction mixture was cooled to room temperature, diluted with water (340 mL), the precipitate was filtered off, washed with water and dried in air at 60° C. to give the 3-bromo-7-trifluoromethyl-5-(4-trifluoromethyl-phenyl)-pyrazolo[1,5-a]pyrimidine (31.77 g, 90%) as a yellow solid. MS (EI) 410.0 [(M)+], 412.0 [(M+2)+]; mp 136° C.

Provenance & Evidence