Reaktion #812852

Reaktionsgleichung

water

N,N'-dicyclohexylcarbodiimide

4-(4-nitrophenylazo)benzoic acid

4-hydroxybenzaldehyde

→

4-[4-(4-nitrophenylazo)benzoyloxy]benzaldehyde

Ausbeute 97.6%

Lösungsmittel

dichlormethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted three times with 50 ml of dichloromethane each time
2. 2
   Waschenwashed twice with 100 ml of water each time
3. 3
   Trocknendried over magnesium sulphate
4. 4
   Filtrationfiltered
5. 5
   Einengenthe filtrate is concentrated
6. 6
   SonstigeChromatographic purification of the residue on silica gel
7. 7
   Sonstigewith hexane/ethyl acetate (vol. 1:1) and two-fold recrystallization from ethanol of the fractions which

Vorschrift

0.6 g of N,N'-dicyclohexylcarbodiimide is added at room temperature while stirring to a solution of 1.0 g of 4-(4-nitrophenylazo)benzoic acid, 0.3 g of 4-hydroxybenzaldehyde and 0.04 g of 4-dimethylaminopyridine in 20 ml of dichlormethane. The reaction mixture is stirred at room temperature overnight, poured into 100 ml of water and then extracted three times with 50 ml of dichloromethane each time. The organic phases are combined, washed twice with 100 ml of water each time, dried over magnesium sulphate, filtered and the filtrate is concentrated. Chromatographic purification of the residue on silica gel with hexane/ethyl acetate (vol. 1:1) and two-fold recrystallization from ethanol of the fractions which are pure according to thin-layer chromatography gives 0.9 g of 4-[4-(4-nitrophenylazo)benzoyloxy]benzaldehyde.

Quelle