تفاعل #460470

معادلة التفاعل

oxygen

1,4-diiodobenzene

iodotrifluoroethylene

→

1,4-BIS(TRIFLUOROVINYL)BENZENE

المردود 65.0%

المذيبات

Glyme

ظروف التفاعل

المعالجة

1. 1
   أخرىA 5 liter 3-necked round bottom flask is fitted with a mechanical stirrer
2. 2
   درجة الحرارةa nitrogen padded reflux condenser
3. 3
   أخرىThe flask is then purged with nitrogen for 15 minutes
4. 4
   أخرىget
5. 5
   درجة الحرارةwarm
6. 6
   workup.WAITAfter 2 hours a white precipitate begins
7. 7
   أخرىto form
8. 8
   workup.STIRRINGAfter stirring
9. 9
   درجة الحرارةwithout heat for 4 hours
10. 10
    أخرىpurge
11. 11
    workup.STIRRINGThe mixture is stirred overnight
12. 12
    أخرىresulting in the formation of a large amount of suspended solid
13. 13
    workup.STIRRINGto stir an additional 24 hours
14. 14
    ترشيحafter which it is filtered
15. 15
    غسيلthe precipitate is washed with hexane (3 times with 50 ml each wash)
16. 16
    أخرىevaporated at 30° C. on a rotary evaporator
17. 17
    أخرىto provide a residue which
18. 18
    أخرىis purified by column chromatography (neutral alumina, hexane eluent)
19. 19
    أخرىto give 7.50 g of CF2 =CF--Ph--CF=CF2 as product (0.0315 mole, 65% yield)
20. 20
    أخرىgives the following spectrum
21. 21
    workup.WAITif left

الإجراء التجريبي

A 5 liter 3-necked round bottom flask is fitted with a mechanical stirrer, a nitrogen padded reflux condenser and a rubber septum. Glyme (100 ml) and activated zinc granules (11.50 g, 0.18 mole) are added to the flask along with a magnetic stirring bar. The flask is then purged with nitrogen for 15 minutes, after which time iodotrifluoroethylene (20.3 g, 0.098 mole) is added slowly via syringe through the septum. After 20 minutes of stirring the mixture begins to turn brown and get warm. After 2 hours a white precipitate begins to form. After stirring is continued without heat for 4 hours, the flask is opened under a slow nitrogen purge and 1,4-diiodobenzene (16.0 g, 0.0485 mole) ia added along with palladium tetrakis(triphenylphosphine) (0.57 g, 0.00049 mole). The mixture is stirred overnight, resulting in the formation of a large amount of suspended solid. The reaction is allowed to stir an additional 24 hours, after which it is filtered, and the precipitate is washed with hexane (3 times with 50 ml each wash). The filtrates are combined and evaporated at 30° C. on a rotary evaporator to provide a residue which is purified by column chromatography (neutral alumina, hexane eluent) to give 7.50 g of CF2 =CF--Ph--CF=CF2 as product (0.0315 mole, 65% yield). This product is analysed by GC/MS and gives the following spectrum: m/e: 238 (100%); 188 (12.0%); 187 (46.4%); 169 (92.0%); 138 (18.8%); 99 (16.3%); 81 (12.3%); 69 (30.1%). The material is found to be air sensitive, fuming acid gasses if left exposed to oxygen.

المصدر