反应详情

6-(2,2,2-trifluoroethoxy)-4(3H)-pyrimidinethione (see Example 1B) (3 g) and 1,4-dibromo-3,4,4-trifluorobutane (see Example 3A) (3.86 g) were added to acetone (50 cm3) containing potassium carbonate (1.97 g) and the mixture stirred at ambient temperature for 7 hours. After standing for a further 16 hours, tlc showed the reaction to be incomplete, so the mixture was heated to reflux for 5 hours. The reaction was then allowed to cool, inorganic solids were filtered off and washed with more acetone. Evaporation of the combined organic layers at reduced pressure afforded a brown oil which was chromatographed on silica gel, eluting with 1:4 ethyl acetate:hexane. This gave the title pyrimidine (3.05 g). M+ =399; 1H NMR (CDCl3): δ2.2-2.4(2H,m); 3.25-3.50(2H,m); 4.68-4.95(1H,m); 4.8(2H,q); 6.73(1H,s); 8.58(1H,s); (oil).

1. waitAfter standing for a further 16 hours
2. customthe reaction
3. temperaturewas heated
4. temperatureto reflux for 5 hours
5. temperatureto cool
6. filtrationinorganic solids were filtered off
7. washwashed with more acetone
8. customEvaporation of the combined organic layers at reduced pressure
9. customafforded a brown oil which
10. customwas chromatographed on silica gel
11. washeluting with 1:4 ethyl acetate