Boron tribromide → HCID 135554909, compound

Participants

Reaction Steps

1.8 g of 3-{2-[N-(2- (4-chlorophenyl)-ethyl)-N-methylamino]-ethyloxy}-5-(-4-methoxyphenyl)-2-methylpyrazole (see Example 24) were dissolved in 100 ml of dichloromethane. 10 ml of a 1 molar solution of boron tribromide in dichloromethane were added to the solution. The reaction mixture was allowed to stand for 12 hours and then placed in water and extracted with dichloromethane. The aqueous phase was separated, rendered alkaline and extracted three times with a mixture of dichloromethane and methanol, and the combined organic phases were dried and concentrated. The crude title compound obtained as an oil was purified by chromatography on silica gel using dichloromethane/methanol. The purified title compound was reacted in accordance with the method described in Example 4 C) with an equimolar quantity of L-(+)-tartaric acid to form a salt, and the resulting salt was crystallized from a mixture of diethyl ether and isopropanol. 1.15 g of 3-{2-[N-(2-(4-chlorophenyl)-ethyl)-N-methylamino]-ethyloxy}-5-(4-hydroxyphenyl)-2-methylpyrazole×1.3 hydrogen tartrate were obtained having a melting point of 90° to 91° C.

Provenance & Evidence