Reaktion #65222

Reaktionsgleichung

4-Chloroacetophenone

5-Methylsulfonyl-3-(trifluoromethyl)isothiazole

acetic acid

→

title compound

1-(4-Chlorophenyl)-2-(3-(trifluoromethyl)-5-isothiazolyl)ethanone

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe oil of a 4.0 g (100 mmol) portion of 60 percent in mineral oil sodium hydride was removed by triple extraction with hexane
2. 2
   Temperaturthe mixture was heated
3. 3
   Temperaturat reflux
4. 4
   Temperaturto cool
5. 5
   workup.ADDITIONwas added
6. 6
   Temperaturthe mixture was heated
7. 7
   Temperaturat reflux
8. 8
   workup.STIRRINGwith stirring for 3 hr
9. 9
   Temperaturto cool
10. 10
    Sonstigethe layers that formed
11. 11
    Sonstigewere separated
12. 12
    ExtraktionThe aqueous layer was extracted with 2×100 mL of ether
13. 13
    Waschenwashed with aqueous sodium bicarbonate solution
14. 14
    Trocknendried over sodium sulfate
15. 15
    Filtrationfiltered
16. 16
    Einengenconcentrated by evaporation under reduced pressure
17. 17
    Sonstigeto obtain a residue
18. 18
    WaschenThis residue was washed with hexane
19. 19
    Sonstigecrystallized from a 1:1 mixture of dichloromethane and hexane

Vorschrift

The oil of a 4.0 g (100 mmol) portion of 60 percent in mineral oil sodium hydride was removed by triple extraction with hexane and was replaced with 100 mL of tetrahydrofuran. 4-Chloroacetophenone (4.33 g, 28 mmol) was added and the mixture was heated at reflux with stirring for 1 hr and then allowed to cool. 5-Methylsulfonyl-3-(trifluoromethyl)isothiazole (4.57 g, 19.8 mmol) dissolved in a small amount of tetrahydrofuran was added and the mixture was heated at reflux with stirring for 3 hr and then allowed to cool. The mixture was next acidified with 60 mL of 10 percent aqueous acetic acid and the layers that formed were separated. The aqueous layer was extracted with 2×100 mL of ether and the organic fractions were combined, washed with aqueous sodium bicarbonate solution, dried over sodium sulfate, filtered, and concentrated by evaporation under reduced pressure to obtain a residue. This residue was washed with hexane and crystallized from a 1:1 mixture of dichloromethane and hexane to obtain 3.19 g (53 percent of theory) of the title compound as a solid melting at 109°-110° C.

Quelle