Reaktion #414217

Reaktionsgleichung

4-(3-chlorophenyl)-3-(ethoxycarbonyl)-2,6-dimethyl-1,4-dihydropyridine-5-carboxylic acid

carbonyldiimidazole

THF

→

Ethyl 4-(3-chlorophenyl)-5-(2-hydroxyethoxycarbonyl)-2,6-dimethyl-1,4-dihydropyridine-3-carboxylate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe mixture is evaporated
2. 2
   Waschenthe mixture is washed twice with 50 ml of water each time
3. 3
   TrocknenAfter drying over Na2SO4
4. 4
   workup.DISTILLATIONthe solvent is distilled off
5. 5
   workup.DISSOLUTIONthe residue (3.55 g) is dissolved in 10 ml of abs
6. 6
   workup.ADDITIONAfter addition of 100 ml of ethylene glycol and 100 mg of NaH
7. 7
   workup.ADDITIONmixed with 100 ml of ethyl acetate
8. 8
   Extraktionextracted twice
9. 9
   workup.STIRRINGby shaking with 100 ml of water each time
10. 10
    TrocknenAfter drying over sodium sulphate
11. 11
    Sonstigethe extract is evaporated

Vorschrift

3.4 g (10 mmol) of 4-(3-chlorophenyl)-3-(ethoxycarbonyl)-2,6-dimethyl-1,4-dihydropyridine-5-carboxylic acid and 2 g (10 mmol) of carbonyldiimidazole are stirred overnight at room temperature in 50 ml of abs. THF. The mixture is evaporated, the residue is taken up in 50 ml of ethyl acetate and the mixture is washed twice with 50 ml of water each time. After drying over Na2SO4, the solvent is distilled off and the residue (3.55 g) is dissolved in 10 ml of abs. THF. After addition of 100 ml of ethylene glycol and 100 mg of NaH, the mixture is stirred at room temperature for 3 h, mixed with 100 ml of ethyl acetate and extracted twice by shaking with 100 ml of water each time. After drying over sodium sulphate, the extract is evaporated. The residue is homogeneous in the TLC and is further processed directly. Yield: 2.95 g (83% of theory)

Quelle