A mixture of compound, 2,4-dichloro-6-phenyl-pyrimidine (13 g, 57.77 mmol), piperidin-4-ol (2.9 g, 28.88 mmol) and triethylamine (32.14 mL, 231.11 mmol) in butanol (110 mL) was stirred at 120° C. for 12 hours under nitrogen atmosphere. The reaction mixture was then poured into water (250 mL) and extracted with ethyl acetate (3×50 mL). The organic layers were collected, combined, washed with water (50 mL), dried over anhydrous sodium sulphate, and concentrated under vacuum. The residue thus obtained was purified by column chromatography using ethyl acetate-petroleum ether to give the two compounds, 1-(4-chloro-6-phenyl-pyrimidin-2-yl)-piperidin-4-ol and 1-(2-chloro-6-phenyl-pyrimidin-4-yl)-piperidin-4-ol in ratio 1:4 (overall yield: 51%).
