Hydrochloric Acid → 3-[1-(4-benzyloxybenzyl)-3-phenyl-1H-pyrazol-4-yl]propionic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of diethyl 2-[1-(4-benzyloxybenzyl)-3-phenyl-1H-pyrazol-4-ylmethyl]malonate (9.41 g), 4N aqueous potassium hydroxide solution (30 ml), and ethanol (30 ml) was refluxed for 1 hour. The reaction mixture was acidified with dilute hydrochloric acid, which was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated aqueous sodium chloride solution, dried (MgSO4), then concentrated. The residue was dissolved in pyridine (20 ml), which was stirred at 110° C. for 2 hours. After removal of the solvent under reduced pressure, the residue was extracted with ethyl acetate. The ethyl acetate layer was washed with dilute hydrochloric acid, then with saturated aqueous sodium chloride solution, dried (MgSO4), then concentrated. The crystals obtained were collected by filtration to yield 3-[1-(4-benzyloxybenzyl)-3-phenyl-1H-pyrazol-4-yl]propionic acid (7.52 g, yield: 99%). This was recrystallized from ethyl acetate-hexane. Melting point: 147–148° C.

Provenance & Evidence