N,N-Dimethylaniline → 7-Chloro-5-(4-chlorophenyl)pyrazolo[1,5-a]pyrimidine

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-(4-chloro-phenyl)-7-hydroxy-pyrazolo[1,5-a]pyrimidine-3-carboxylate (9.53 g, 0.03 mol), phosphorous oxychloride (11.0 mL, 0.12 mol), and N,N-dimethylaniline (1.3 mL, 0.01 mol) was stirred for 2 h at 100° C. The mixture was evaporated in vacuo and the residue was partitioned between water and dichloromethane. The organic phase was washed with water, dried (Na2SO4) and evaporated in vacuo. The remaining solid was crystallized from ethyl acetate/hexane to give 7-chloro-5-(4-chloro-phenyl)-pyrazolo[1,5-a]pyrimidine (6.80 g, 67%). Pale-yellow solid, MS (ISP) 336.0 [(M+H)+]; mp 133-135° C.

Provenance & Evidence