Dimethylformamide → ethyl 3-benzyloxy-1-phenyl-1H-pyrazole-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of ethyl 3-hydroxy-1-phenyl-1H-pyrazole-4-carboxylate (7.76 g), benzyl bromide (3.97 ml), potassium carbonate (6.91 g) and N,N-dimethylformamide (75 ml) was stirred overnight at 50° C. The reaction mixture was poured into water and the mixture was extracted with ethyl acetate. The ethyl acetate layer was dilute hydrochloric acid, and then washed successively with saturated brine, dried (MgSO4) and concentrated. The residue was subjected to silica gel column chromatography, and ethyl 3-benzyloxy-1-phenyl-1H-pyrazole-4-carboxylate (8.29 g, yield 77%) was obtained as colorless crystals from a fraction eluted with ethyl acetate-hexane (1:1, volume ratio). The crystals were recrystallized from ethyl acetate-hexane. melting point: 113–114° C.

Provenance & Evidence