Reaktion #94491

Reaktionsgleichung

DL-cysteine ethyl ester hydrochloride

1-hexyne

2,2'-azobis-(2-methylpropionitrile)

→

(1-hexenyl) sulfide

Lösungsmittel

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling, most of the solvent
2. 2
   Sonstigewas evaporated in vacuo
3. 3
   workup.ADDITIONThe residue was treated with 150 ml of 1N sodium carbonate solution
4. 4
   Extraktionextracted three times with ethyl acetate
5. 5
   Waschenwashed with 3 × 50 ml of saturated brine
6. 6
   Trocknendried over anhydrous sodium sulfate
7. 7
   Sonstigeevaporated in vacuo

Vorschrift

A mixture of 12.80 g (68.93 mmol) of DL-cysteine ethyl ester hydrochloride, 25.60 g (311.62 mmol) of 1-hexyne, and 50 mg of 2,2'-azobis-(2-methylpropionitrile) in 250 ml of absolute dioxane was stirred at 60°-65°. under inert gas atmosphere for 20 minutes. After cooling, most of the solvent was evaporated in vacuo. The residue was treated with 150 ml of 1N sodium carbonate solution and extracted three times with ethyl acetate. The organic phases were combined, washed with 3 × 50 ml of saturated brine, dried over anhydrous sodium sulfate and evaporated in vacuo to give 15.90 g (99%) of crude (ethyl 2-aminopropanoate-3-yl) (1-hexenyl) sulfide as a thick pale yellow oil which can be used without further purification in the next step. NMR spectroscopical studies showed that the product is approximately a 1:1 mixture of geometrical isomers.

Quelle