反应详情

4-Hydroxy-6-methyl-2-methylthiopyrimidine (10.0 g, 64.13 mmol), prepared by the procedure described in Example 158A, was dissolved in ~45 mL (483 mmol, 7 equivalents) of phosphorus oxychloride under nitrogen and heated at reflux for 6.5 hours. The phosphorus oxychloride was distilled off and the remaining residue was dissolved in ether and poured onto ice. The aqueous phase was extracted several times with ether. The combined ether extracts were dried over magnesium sulfate and the 4-chloro-6-methyl-2-methylthiopyrimidine crystallized from the ether to afford 6.91 g (62%) as pale orange needles. 1H NMR (CDCl3, 300 MHz) δ 2.45 (s, 3H), 2.58 (s, 3H), 6.77 (s, 1H). MS (DCl/NH3) m/e 175 (M+H)+. The chloro-compound was reacted with n-butylamine by the procedure described in Example 158C to give 4-butylamino-6-methyl-2-methylthiopyrimidine.

1. temperatureheated
2. temperatureat reflux for 6.5 hours
3. distillationThe phosphorus oxychloride was distilled off
4. dissolutionthe remaining residue was dissolved in ether
5. additionpoured onto ice
6. extractionThe aqueous phase was extracted several times with ether
7. dry with materialThe combined ether extracts were dried over magnesium sulfate
8. customthe 4-chloro-6-methyl-2-methylthiopyrimidine crystallized from the ether
9. customto afford 6.91 g (62%) as pale orange needles