Water → HCID 13749204, compound

Participants

Reaction Steps

4-Chloro-1-ethyl-5-(4-trifluoromethylbenzoyl)-1H-pyrazolo[3,4-b]pyridine (3.10 g) was refluxed for 2 hours in 300 ml of acetic acid containing 9 g of hydroxylamine hydrochloride and 0.6 g of p-toluenesulfonic acid monohydrate. At the end of this time the reaction mixture was poured into water and extracted with dichloromethane. The organic phase was washed well with water, dried, evaporated, and purified by chromatography over 230-400 mesh silica gel (10% ethyl acetate/dichloromethane). In this way, 2.15 g of product was obtained, mp 243°-245°. Recrystallization from ethyl acetate gave analytically pure product, mp 244°-245° C.

Provenance & Evidence