4-[(4-Bromo-3,4,4-trifluorobutyl)thio]-6-(2,2,2-trifluoroethoxy)-pyrimidin → 4-[(4,4-Difluoro-3-butenyl)thio]-6-(2,2,2-trifluoroethoxy)-pyrimidine

The product from step 1 (2.8 g) was treated with zinc powder (1.376 g) in methanol (100 cm3) containing zinc iodide (catalytic amount). The mixture was heated under reflux for 7 hours and glc then indicated that only about 70% conversion had occurred. A further 0.459 g of zinc powder was added and heating continued for 6 hours. The cooled reaction mixture was filtered through a plug of celite, which was washed with more ethanol. The combined organic solutions were evaporated under reduced pressure to give a yellow oil. Purification by chromatography on silica gel, eluting with 1:10 ethyl acetate:hexane gave Compound No. 13 (1.1 g). M+ =300; 1H NMR (CDCl3): δ2.4(2H,m); 3.2(2H,t); 4.2-4.35(1H,m); 4.78(2H,q); 6.7(1H,s); 8.55(1H,s); (oil).

1. temperatureThe mixture was heated
2. temperatureunder reflux for 7 hours
3. temperatureheating
4. customThe cooled reaction mixture
5. filtrationwas filtered through a plug of celite, which
6. washwas washed with more ethanol
7. customThe combined organic solutions were evaporated under reduced pressure
8. customto give a yellow oil
9. customPurification by chromatography on silica gel
10. washeluting with 1:10 ethyl acetate
11. customhexane gave Compound No

ORD record

ord-03bb820092ac4277a0c1e3d260a1fbf2

Source dataset

uspto-grants-1997_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05684011