Phosphorus oxychloride → 4-Chloro-2-{[(3,5-dichloropyridin-4-yl)methyl]sulfanyl}-6-methylpyrimidine
Reaction equation
[Cl:1][C:2]1[CH:3]=[N:4][CH:5]=[C:6]([Cl:18])[C:7]=1[CH2:8][S:9][C:10]1[N:15]=[C:14](O)[CH:13]=[C:12]([CH3:17])[N:11]=1.P(Cl)(Cl)([Cl:21])=O>>[Cl:21][C:14]1[CH:13]=[C:12]([CH3:17])[N:11]=[C:10]([S:9][CH2:8][C:7]2[C:2]([Cl:1])=[CH:3][N:4]=[CH:5][C:6]=2[Cl:18])[N:15]=1Participants
3
Conditions
- Temperature
- 75 °C
Procedure
A mixture of 2-{[(3,5-dichloropyridin-4-yl)methyl]sulfanyl}-6-methylpyrimidin-4-ol (2.0 g, 6.62 mmol) and phosphoryl trichloride (20 mL) was heated at 75° C. for 1 hour. The solvent was evaporated, and the crude residue was extracted into ethyl acetate (2×100 mL). The organic layer was washed with 10% sodium bicarbonate solution and brine. The organic layer was separated, dried over anhydrous sodium sulfate, and filtered. The solvent was evaporated, and the residue was purified by CombiFlash using 0-5% methanol in dichloromethane to provide 4-chloro-2-{[(3,5-dichloropyridin-4-yl)methyl]sulfanyl}-6-methylpyrimidine as a white solid (1.01 g, 47.1% yield); 1H NMR (400 MHz, DMSO-d6): δ 2.45 (s, 3H), 4.70 s, 2H), 7.40 (s, 1H), 8.66 (d, 211); M+1 321.2.