反应详情

(E)-1-Ethoxy-4,4,5,5,5-pentafluoropent-1-en-3-one (1.09 g, 5 mmol) in anhydrous ethyl ether (5 mL) was treated with 1-((E)-3-methylthiobut-1-enyl)pyrrolidine (0.85 g, 5 mmol) in 2 mL dry ether at −15° C. over a period of 5 min and the reaction was continued for 20 min. Then the temperature was allowed to rise to room temperature and the reaction continued for 3 h. The solvent was removed under reduced pressure and the residue re-dissolved in anhydrous DMF (5 mL). Ammonium acetate (0.58 g, 7.5 mmol) was added and the mixture stirred at room temperature over a weekend. Water was added and mixture extracted with ether three times. The combined organic layer was washed with brine, dried over anhydrous Na2SO4, filtered, concentrated, and purified on silica gel eluted with 8% EtOAc in hexane (v/v) to give 0.16 g of the desired 5-(1-methylthioethyl)-2-pentafluoroethylpyridine (A) as brownish colored oil in 12 percent yield. GC-MS: mass calcd for C10H11F2N3S [M]+ 271. Found 271.

1. customto rise to room temperature
2. waitthe reaction continued for 3 h
3. customThe solvent was removed under reduced pressure
4. dissolutionthe residue re-dissolved in anhydrous DMF (5 mL)
5. extractionmixture extracted with ether three times
6. washThe combined organic layer was washed with brine
7. dry with materialdried over anhydrous Na2SO4
8. filtrationfiltered
9. concentrationconcentrated
10. custompurified on silica gel
11. washeluted with 8% EtOAc in hexane (v/v)