A mixture of 2-(3-pyrazolyl)ethanol and 2-(4-pyrazolyl)ethanol (2.4:1) (2.50 g) was dissolved in DMF (30 ml). To the solution were added, while stirring, triethylamine (2.26 g) and trityl chloride (6.22 g). The mixture was stirred at 25° C. for one hour, then at 40° C. for one hour. The reaction mixture was diluted with water, which was subjected to extraction with ethyl acetate. The organic layer was washed with an aqueous saline solution, which was dried over anhydrous magnesium sulfate, followed by concentration under reduced pressure. The concentrate was purified by means of a column chromatography (carrier: silica gel, 300 g, developing solvent: ethyl acetate-hexane, 1:1) to afford 2-(1-triphenylmethyl-3-pyrazolyl)ethanol (3.75 g) and 2-(1-triphenylmethyl-4-pyrazolyl)ethanol (1.42 g).
