Reaktion #416786

Reaktionsgleichung

4-(4-(1,1-dimethylethyl)-2-thiazolyl)-1-phenylmethyl-1,2,3,6-tetrahydropyridine

K2CO3

chloroformic acid vinyl ester

→

4-(4-(1,1-Dimethylethyl)-2-thiazolyl)-1,2,3,6-tetrahydropyridine

Lösungsmittel

1,2-dichloroethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent is evaporated
2. 2
   Sonstigethe residue partitioned between water and hexane
3. 3
   Extraktionand the water phase extracted with hexane
4. 4
   WaschenThe combined organic layers are washed with saturated brine solution
5. 5
   Filtrationfiltered
6. 6
   Trocknendried (Na2SO4)
7. 7
   SonstigeThe solvent is evaporated
8. 8
   workup.ADDITIONthe oily residue is added under ice-
9. 9
   Temperaturcooling to 20% aqueous hydrochloric acid
10. 10
    TemperaturThe mixture is heated on a steam bath for 4 hours
11. 11
    Extraktionextracted once with dichloromethane
12. 12
    FiltrationThe aqueous acidic solution is filtered
13. 13
    Extraktionextracted with ethyl ether
14. 14
    SonstigeAfter evaporation of ether
15. 15
    Sonstigethe heading compound is obtained as an oily residue
16. 16
    Sonstigeis 170°-171°

Vorschrift

5.5 g 4-(4-(1,1-dimethylethyl)-2-thiazolyl)-1-phenylmethyl-1,2,3,6-tetrahydropyridine, 2.5 g K2CO3 and 50 ml 1,2-dichloroethane are treated dropwise at -10° to -7° under stirring with 3.75 ml chloroformic acid vinyl ester. The mixture is stirred at -10° to -7° for 3 hours. The solvent is evaporated, the residue partitioned between water and hexane. and the water phase extracted with hexane. The combined organic layers are washed with saturated brine solution, filtered and dried (Na2SO4). The solvent is evaporated and the oily residue is added under ice-cooling to 20% aqueous hydrochloric acid. The mixture is heated on a steam bath for 4 hours, then cooled to room temperature and extracted once with dichloromethane.The aqueous acidic solution is filtered, made alkaline with aqueous NaOH and extracted with ethyl ether. After evaporation of ether, the heading compound is obtained as an oily residue. M.p. of the hydrogenmaleinate is 170°-171°.

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