Reaktion #1069348

Reaktionsgleichung

3,3'-dithiodipropionic acid

chlorobenzene

pyridine

thionyl chloride

thionyl chloride

→

3-n-octylisothiazolone

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeTo a 500 ml flask fitted with a mechanical stirrer, nitrogen inlet, and an outlet to a 10% sodium hydroxide trap
2. 2
   workup.ADDITIONwas added
3. 3
   workup.STIRRINGwas stirred overnight
4. 4
   Sonstigewas reheated to 45° C.
5. 5
   Sonstigesparged for 15 min with nitrogen
6. 6
   SonstigeThe remaining thionyl chloride was removed
7. 7
   workup.WAITby stripping under house vaccuum for 1 hr
8. 8
   workup.ADDITION50 ml of chlorobenzene was charged
9. 9
   TemperaturThe mixture was cooled to -20° C.
10. 10
    workup.ADDITION6.8 g (0.096 M) of chlorine was added over 16 min
11. 11
    workup.STIRRINGAfter stirring 0.5hr the mixture
12. 12
    Temperaturwas warmed to 0°-5° C.
13. 13
    workup.ADDITIONa solution of 24.6 g (0.188 M) of n-octyl amine and 9.2 g (0.188 M) of triethyl amine in 100 ml of chlorobenzene was added dropwise such that the reaction temperature
14. 14
    Sonstigeremained below 5° C.
15. 15
    workup.ADDITION(addition time 1.75 hr)
16. 16
    Temperaturto warm
17. 17
    Temperaturheated to 35° C
18. 18
    workup.WAITChlorine (13.5 g, 0.19 M) was then fed over 40 min at 35° C.
19. 19
    workup.STIRRINGthe mixture was stirred for an additional 1 hr
20. 20
    WaschenThe reaction mixture was washed with 3×400 ml of water
21. 21
    Sonstigethe solvent was removed under vaccuum

Vorschrift

To a 500 ml flask fitted with a mechanical stirrer, nitrogen inlet, and an outlet to a 10% sodium hydroxide trap was charged 20g(0.095M) of 3,3'-dithiodipropionic acid, 200 ml of chlorobenzene and 0.25 ml of pyridine. An addition funnel containing 24.9 g (0.21 M) of thionyl chloride was added and the thionyl chloride was added dropwise. The mixture was warmed to 45° C. and stirred for 2.5 hours. The mixture was not homogeneous and was stirred overnight. (The reaction was still not quite homogeneous but was carried on at this point.) The mixture was reheated to 45° C. and sparged for 15 min with nitrogen. The remaining thionyl chloride was removed by stripping under house vaccuum for 1 hr and then 50 ml of chlorobenzene was charged. The mixture was cooled to -20° C. and 6.8 g (0.096 M) of chlorine was added over 16 min. After stirring 0.5hr the mixture was warmed to 0°-5° C. and a solution of 24.6 g (0.188 M) of n-octyl amine and 9.2 g (0.188 M) of triethyl amine in 100 ml of chlorobenzene was added dropwise such that the reaction temperature remained below 5° C. (addition time 1.75 hr). The solution was allowed to warm and then heated to 35° C. During this time the reaction thickened and then thinned out. Chlorine (13.5 g, 0.19 M) was then fed over 40 min at 35° C. and the mixture was stirred for an additional 1 hr. The reaction mixture was washed with 3×400 ml of water and then the solvent was removed under vaccuum to yield 36g of 3-n-octylisothiazolone as a dark oil. Analysis by capillary gas chromatography indicated a yield of 21.8 g (53.7%) of 3-n-octylisothiazolone.

Quelle