2-Butyn-1-ol → 4-(2-Butynyloxy)-6-chloropyrimidine

1.05 g of sodium hydride (60% oil suspension) was suspended in 24 ml of tetrahydrofuran. 8 ml of tetrahydrofuran solution of 1.42 g of 2-butyn-1-ol was added dropwise at room temperature therein slowly, and the mixture was stirred for 20 minutes. Into the mixture was added dropwise 8 ml of tetrahydrofuran solution of 3 g of 4,6-dichloropyrimidine at 0° C. slowly, and stirred for 4 hours. The reaction mixture was poured into a saturated ammonium chloride aqueous solution, and the mixture was extracted with chloroform three times. The organic layers were washed with water, dried over anhydrous magnesium sulfate and concentrated. The residue was subjected to silica gel column chromatography to obtain 3.16 g of 4-chloro-6-(2-butynyloxy) pyrimidine.