反应详情

50.6 g (0.33 mol) of phosphoryl trichloride are added under a protecting gas (nitrogen) to a suspension of 69 g (1 mol) of 1,2,4-triazole in 800 ml of dry acetonitrile at an internal temperature of 0°-50° C. During a period of 1 hour, 101.2 g (1 mol) of triethylamine are then added dropwise. After stirring for a further 40 minutes at room temperature, 18.9 g (0.15 mol) of thymine are added. The suspension is stirred for 24 hours at room temperature, 25 ml of water are added and the mixture is stirred for a further 10 minutes and then filtered. The yellow residue is suspended in 400 ml of water, stirred and filtered off by suction after 1 hour. 1.72 g of 5-methyl-4-(1,2,4-triazol-1-yl)-pyrimidin-2-(1H)-one are obtained as a yellow powder with melting point 258°-264° C. The acetonitrile solution is concentrated, the residue is suspended in 400 ml of water, stirred and filtered off by suction. In this manner, a further 7.21 g of the compound are obtained. The title compound can be recrystallized from dimethylformamide and then melts at 275°-280° C. 1H NMR (60 MHz, d6 -DMSO), δ[ppm]: approx. 12.0 (s, broad, 1H), 9.33 (s, 1H), 8.40 (s, 1H), 8.13 (s, 1H), 2.3 (s, 3H).

1. stirringThe suspension is stirred for 24 hours at room temperature
2. stirringthe mixture is stirred for a further 10 minutes
3. filtrationfiltered
4. stirringstirred
5. filtrationfiltered off by suction after 1 hour