Reacción #950898

Ecuación de reacción

N-methylacrylamide

triethylamine

trimethylsilyl chloride

→

N-methyl-N-trimethylsilylacrylamide

Rendimiento 45.0%

Disolventes

acetonitrile

acetonitrile

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe reaction vessel was fitted with a reflux condenser
2. 2
   OtroA white precipitate formed almost immediately
3. 3
   Temperaturato increase throughout the addition
4. 4
   workup.ADDITIONAfter the addition
5. 5
   FiltraciónThe mixture was filtered
6. 6
   Filtraciónvacuum filtration in a dry bag
7. 7
   workup.ADDITIONfilled with nitrogen
8. 8
   OtroThe white precipitate was collected as a filter cake
9. 9
   ConcentraciónThe orange colored filtrate concentrated in vacuo
10. 10
    Otrogave a dark red material
11. 11
    workup.DISTILLATIONThe crude mixture was subjected to vacuum fractional distillation
12. 12
    workup.DISTILLATIONThe first fraction distilled at 22°-35° C. at 0.3 mm Hg
13. 13
    workup.DISTILLATIONThe second fraction distilled at 35°-45° C. at 0.3 mm Hg
14. 14
    workup.DISTILLATIONThe third fraction distilled at 70°-80° C. at 0.3 mm Hg
15. 15
    OtroThe reaction gave about 45% yield

Procedimiento

N-methylacrylamide (50.9 g, 0.6 mole) and triethylamine (67 g, 0.67 mole) were added to 300 mL of acetonitrile in a 500 mL round-bottomed flask. The reaction vessel was fitted with a reflux condenser topped with a rubber stopper that contained two needles, one connected to a source of nitrogen gas and other to an oil bubbler. A solution of trimethylsilyl chloride (72.4 g, 0.67 mole) in a 50 mL acetonitrile was added dropwise to this mixture. A white precipitate formed almost immediately. The amount of precipitate continued to increase throughout the addition and the color of the solution changed from colorless to orange. After the addition was completed, the resulting slurry was allowed to stir at room temperature for six hours. The mixture was filtered using vacuum filtration in a dry bag filled with nitrogen. The white precipitate was collected as a filter cake. NMR-T60 analysis indicated the filter cake was the triethylammonium chloride, the expected by-product. The orange colored filtrate concentrated in vacuo gave a dark red material. The crude mixture was subjected to vacuum fractional distillation. The first fraction distilled at 22°-35° C. at 0.3 mm Hg. NMR analysis showed it was mostly acetonitrile and a small amount of product. The second fraction distilled at 35°-45° C. at 0.3 mm Hg and appeared to be the desired pure product on NMR analysis. The third fraction distilled at 70°-80° C. at 0.3 mm Hg. NMR analysis showed it was N-methyl acrylamide. The pot contained uncharacterized polymerized material as a black viscous material. The reaction gave about 45% yield.

Fuente