Hydrochloric Acid → ethyl 1-benzyl-3-benzyloxy-1H-pyrazol-4-ylacetate

Participants

Reaction Steps

A mixture of 1-benzyl-3-benzyloxy-1H-pyrazol-4-ylacetonitrile (13.0 g), 4N aqueous sodium hydroxide solution (100 ml), tetrahydrofuran (100 ml) and ethanol (100 ml) was refluxed for 3 days. After cooling, the mixture was neutralized with dilute hydrochloric acid, which was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated aqueous sodium chloride solution, dried (MgSO4) and concentrated. A mixture of the residue, ethyl iodide (5.2 ml), potassium carbonate (11.9 g) and N,N-dimethylformamide (100 ml) was stirred at room temperature for 3 hours. The reaction mixture was poured into water, which was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated aqueous sodium chloride solution, dried (MgSO4), and concentrated. The residue was subjected to silica gel column chromatography to obtain ethyl 1-benzyl-3-benzyloxy-1H-pyrazol-4-ylacetate (14.9 g, yield 99%) as a colorless oily substance from the fraction eluted with ethyl acetate-hexane (1:2, volume ratio).

Provenance & Evidence