Reaktion #85043

Reaktionsgleichung

glyoxalic acid monohydrate

1,3-propanedithiol

para-toluenesulphonic acid

→

1,3-Dithiane-2-carboxylic acid

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturunder reflux for 3 h
2. 2
   Extraktionextracted three times with 100 ml of saturated aqueous sodium bicarbonate solution
3. 3
   WaschenThe combined aqueous phases were washed with 200 ml of diethyl ether
4. 4
   Extraktionextracted four times with 200 ml of ethyl acetate
5. 5
   TrocknenThe combined organic phases were dried over magnesium sulphate
6. 6
   Filtrationfiltered
7. 7
   Sonstigethe solvent was removed under reduced pressure
8. 8
   SonstigeThe residue was used for the next step without further purification

Vorschrift

9.20 g (100 mmol) of glyoxalic acid monohydrate, 11.1 ml (110 mmol) of 1,3-propanedithiol and 1.72 g (10.0 mmol) of para-toluenesulphonic acid were heated in 200 ml of toluene under reflux for 3 h. The reaction mixture was cooled to RT and extracted three times with 100 ml of saturated aqueous sodium bicarbonate solution. The combined aqueous phases were washed with 200 ml of diethyl ether, acidified with aqueous hydrochloric acid (6N) and extracted four times with 200 ml of ethyl acetate. The combined organic phases were dried over magnesium sulphate and filtered, and the solvent was removed under reduced pressure. The residue was used for the next step without further purification. Yield: 8.0 g (47% of theory)

Quelle