[2-Methyl-5-(4-trifluoromethyl-phenyl)-2H-pyrazol-3-yl]-acetic acid → 2-[2-Methyl-5-(4-trifluoromethyl-phenyl)-2H-pyrazol-3-yl]-ethanol

Participants

Reaction Steps

A solution of [2-methyl-5-(4-trifluoromethyl-phenyl)-2H-pyrazol-3-yl]-acetic acid (286 mg, 1 mmol) in tetrahydrofuran (4 ml) was treated at 0° C. with a 1 M solution of BH3*THF in tetrahydrofuran (2.5 ml, 3 mmol). The cooling bath was removed and the reaction mixture stirred at ambient temperature for 16 h. Careful quenching with MeOH and ice water, twofold extraction with AcOEt, washing with ice water/brine 1/1, drying over magnesium sulfate, and evaporation of the solvent left a crude product which was refluxed for 30 min in MeOH to liberate quantitatively the free alcohol. The solvent was evaporated in vacuo to yield 273 mg (1 mmol, quant.) of the title compound as colorless crystals.

Provenance & Evidence