Ammonium Chloride → 7-Methyl-5-(4-trifluoromethyl-phenyl)-pyrazolo[1,5-a]pyrimidine

Participants

Reaction Steps

To a solution of 7-chloro-5-(4-trifluoromethyl-phenyl)-pyrazolo[1,5-a]pyrimidine (1.49 g, 5.0 mmol) and tetrakis(triphenylphosphin)palladium (1.73 g, 1.5 mmol) in THF (50 mL) was added at 20° C. 2 M dimethylzinc/toluene solution (6.25 mL, 12.5 mmol) and the mixture was refluxed in an atmosphere of argon for 2 h. After the slow addition at 0° C. of sat. aqueous NH4Cl solution (12 mL), the mixture was partitioned between AcOEt and 10% sodium chloride solution. The organic layer was evaporated in vacuo and the residue was chromatographed on silica gel using AcOEt/hexane (1:3 v/v) as eluent to give the title compound (1.17 g, 84%). Pale yellow solid. MS (ISN) 276.1 [(M−H)−]; mp 89-90° C.

Provenance & Evidence