反応 #631836

反応方程式

diethyl ether

2-bromoacetaldehyde-dimethylacetal

sodium hydride

4,5-bis-(p-methoxyphenyl)-thiazoline-2-thione

→

2-[4,5-bis-(p-methoxyphenyl)-thiazol-2-ylthio]-acetaldehyde-dimethylacetal

溶媒

hexamethylphosphoric acid triamide

反応条件

後処理

1. 1
   温度to cool to 20°
2. 2
   温度the reaction temperature being maintained at 25°-30°
3. 3
   温度by cooling
4. 4
   workup.ADDITIONpoured onto ice
5. 5
   その他the organic phase is removed
6. 6
   抽出The aqueous phase is extracted
7. 7
   workup.STIRRINGby shaking again with 200 ml of diethyl ether
8. 8
   洗浄washed with 200 ml of 2 N sodium hydroxide solution
9. 9
   乾燥dried over magnesium sulphate
10. 10
    濃縮concentrated by evaporation
11. 11
    その他The oily crude product is crystallised from hexane

実験手順

20.0 g of 4,5-bis-(p-methoxyphenyl)-thiazoline-2-thione are dissolved in 100 ml of hexamethylphosphoric acid triamide at 35°. The mixture is allowed to cool to 20°, first 11.2 g of 2-bromoacetaldehyde-dimethylacetal and then, in portions, 2.9 g of 50% strength sodium hydride suspension (in mineral oil, de-oiled with hexane) are added, the reaction temperature being maintained at 25°-30° by cooling. The mixture is then stirred at room temperature for 1 hour, poured onto ice, the oil which separates is brought into solution with diethyl ether, and the organic phase is removed. The aqueous phase is extracted by shaking again with 200 ml of diethyl ether. The organic phases are combined, washed with 200 ml of 2 N sodium hydroxide solution, dried over magnesium sulphate and concentrated by evaporation. The oily crude product is crystallised from hexane and made into a slurry with methanol. 2-[4,5-bis-(p-methoxyphenyl)-thiazol-2-ylthio]-acetaldehyde-dimethylacetal having a melting point of 60°-61° is obtained.

出典