Réaction #1483057

Équation de réaction

(Z)-9-oxabicyclo[6.1.0]non-4-ene

methyl benzoate

→

(E)-9-oxabicyclo[6.1.0]non-4-ene

Rendement 40.0%

Solvants

Conditions de réaction

Traitement

1. 1
   AutreNo attempt to degas the solution
2. 2
   AutreThe vessel was irradiated with 254 nm light in a Rayonet RPR-100 UV reactor (Southern New England Ultraviolet Company) under constant stirring
3. 3
   Autrethe irradiation
4. 4
   Autrethrough was then transferred back into the quartz flask and irradiation
5. 5
   AutreAfter 6 hours the irradiation
6. 6
   workup.ADDITIONthe silica was added to a solution of ammonium hydroxide
7. 7
   workup.ADDITIONwas added
8. 8
   workup.STIRRINGstirring
9. 9
   workup.STIRRINGAfter stirring the ether phase
10. 10
    Autrewas decanted
11. 11
    Lavagewashed with water
12. 12
    Séchagedried with magnesium sulfate
13. 13
    Autreevaporated

Mode opératoire

To a 9:1 ether/hexanes solution (250 mL) in a 500 mL quartz reaction vessel, was added (Z)-9-oxabicyclo[6.1.0]non-4-ene (1.0 g) and methyl benzoate (1.1 g) sensitizer. No attempt to degas the solution was made. The vessel was irradiated with 254 nm light in a Rayonet RPR-100 UV reactor (Southern New England Ultraviolet Company) under constant stirring. At 30 minute intervals, the irradiation was stopped and the entire solution was passed through a column packed with silver nitrate (10%) impregnated silica. The solution that passes through was then transferred back into the quartz flask and irradiation was continued. After 6 hours the irradiation was stopped and the silica was added to a solution of ammonium hydroxide and stirred for 5 minutes after which ether was added and stirring continued for 5 more minutes. After stirring the ether phase was decanted, washed with water, dried with magnesium sulfate, and evaporated yielding (E)-9-oxabicyclo[6.1.0]non-4-ene (0.4 g, 40% yield). 1HNMR (400 MHz CDCl3): δ 5.8-5.7 (m, 1H), 5.4-5.2 (m, 1H), 2.9-2.7 (m, 2H) 2.5-2.0 (m, 8H).

Source