تفاعل #3011

معادلة التفاعل

hydrobromic acid

water

phenylmagnesium bromide

phenyl sulfoxide

→

triphenylsulfonium bromide

المذيبات

benzene

ether

dichloromethane

benzene

ظروف التفاعل

المعالجة

1. 1
   أخرىTo a 3-necked 1 L round bottom flask equipped with a still head
2. 2
   أخرىthe diethyl ether removed under vacuo
3. 3
   درجة الحرارةby gently heating
4. 4
   workup.ADDITIONAdditional benzene (150 ml) was added
5. 5
   درجة الحرارةa gentle reflux under nitrogen
6. 6
   workup.ADDITIONOnce the addition
7. 7
   درجة الحرارةthe reaction mixture was heated at
8. 8
   درجة الحرارةa gentle reflux for 3 hours
9. 9
   درجة الحرارةThe reaction mixture was cooled (ice bath temperature)
10. 10
    أخرىAfter separation of the layers
11. 11
    استخلاصthe organic layer extracted
12. 12
    استخلاصextracted with dichloromethane (200 ml)
13. 13
    تجفيفdried (MgSO4 )
14. 14
    تركيزconcentrated in vacuo
15. 15
    أخرىto give the crude product as an off-white solid (14.50 g)
16. 16
    workup.ADDITIONadded
17. 17
    أخرىto precipitate the salt
18. 18
    درجة الحرارةThe suspension was cooled in an ice bath for 1 hour
19. 19
    أخرىto collecting the salt
20. 20
    غسيلwashing with ether

الإجراء التجريبي

To a 3-necked 1 L round bottom flask equipped with a still head was added phenylmagnesium bromide (3 M in diethyl ether, 142 ml, 0.426 mol) followed by dry benzene (150 ml). The flask was connected to a water aspirator and the diethyl ether removed under vacuo by gently heating. Additional benzene (150 ml) was added and the solution brought to a gentle reflux under nitrogen. A solution of phenyl sulfoxide (17.23 g, 85.2 mmol) in benzene (100 ml) was added dropwise over 1.5 hours. Once the addition was complete, the reaction mixture was heated at a gentle reflux for 3 hours. The reaction mixture was cooled (ice bath temperature) while adding a solution of hydrobromic acid (25%, 200 ml). The resulting biphasic mixture was stirred at room temperature overnight. After separation of the layers, the organic layer extracted were combined and extracted with dichloromethane (200 ml), dried (MgSO4 ) and concentrated in vacuo to give the crude product as an off-white solid (14.50 g). The solid was taken up in the minimum mount of warm dichloromethane (100 ml) and four times the volume of ether added to precipitate the salt. The suspension was cooled in an ice bath for 1 hour prior to collecting the salt and washing with ether. In this way, triphenylsulfonium bromide was isolated as a white solid (14.40 g, 49%).

المصدر