Reacción #2692

Ecuación de reacción

carbon dioxide

methyl iodide

potassium carbonate

n-Butyllithium

2,2,6,6-Tetramethylbenzo[1,2-d:4,5-d']-bis(1,3)dithiole

→

4-Methoxycarbonyl-(2,2,6,6-tetramethylbenzo[1,2-d:4,5-d']-bis(1,3)dithiole)

Disolventes

DMF

ether

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONfilled
2. 2
   Otroreaction flask
3. 3
   workup.STIRRINGafter stirring overnight
4. 4
   Filtraciónthe ether was filtered off
5. 5
   LavadoThe solid residue was washed with chloroform
6. 6
   Otrodried under vacuum
7. 7
   workup.STIRRINGwas stirred for 1.5 h at 60° C
8. 8
   workup.WAITThe stirring was continued overnight
9. 9
   FiltraciónThe mixture was filtered
10. 10
    Otrothe solution evaporated
11. 11
    workup.DISSOLUTIONthe residue was dissolved in dichloromethane
12. 12
    LavadoThe organic phase was washed with water (2*30 mL)
13. 13
    Secadodried (Na2SO4)
14. 14
    Otroevaporated
15. 15
    Otroto give
16. 16
    Otroafter additional drying under vacuum a bright green-yellow crystalline pure product

Procedimiento

2,2,6,6-Tetramethylbenzo[1,2-d:4,5-d']-bis(1,3)dithiole (2.0 g, 6.98 mmol) was dissolved in dry ether (50.0 mL) in a dry, argon filled reaction flask. n-Butyllithium (3.07 mL, 2.5M in hexane) was added and the reaction mixture was stirred for 30 min. The solution was poured onto solid carbon dioxide and, after stirring overnight, the ether was filtered off. The solid residue was washed with chloroform and dried under vacuum. The crude product was mixed with potassium carbonate (0.97 g, 6.98 mmol) in dry DMF (20.0 mL) and was stirred for 1.5 h at 60° C. After cooling to ambient temperature, methyl iodide (0.435 mL, 6.98 mmol) was added. The stirring was continued overnight. The mixture was filtered, the solution evaporated and the residue was dissolved in dichloromethane and water. The organic phase was washed with water (2*30 mL), dried (Na2SO4) and evaporated to give after additional drying under vacuum a bright green-yellow crystalline pure product.

Fuente