Reaktion #2376526

Reaktionsgleichung

HCl

DIEA

di-tert-butyldicarbonate

1-(4-(N-Boc-4-piperidinyloxy)-2-methoxyphenyl)cyclopentylcarboxylic acid methyl ester

NaOH

→

1-(4-(N-Boc-4-piperidinyloxy)-2-methoxyphenyl)cyclopentylcarboxylic acid

Lösungsmittel

MeOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was refluxed for 5 days
2. 2
   Sonstigethe solvent was removed under reduced pressure
3. 3
   workup.ADDITIONwere added
4. 4
   SonstigeThe solvent was removed under reduced pressure
5. 5
   Sonstigethe residue was partitioned between EtOAc (50 mL) and 0.25 M aqueous citric acid (25 mL)
6. 6
   WaschenThe organic phase was washed with water (25 mL)
7. 7
   Trocknendried (MgSO4)
8. 8
   Filtrationfiltered
9. 9
   Sonstigethe solvent was removed under reduced pressure

Vorschrift

To a solution of 1-(1-(1-(4-(N-Boc-4-piperidinyloxy)-2-methoxyphenyl)cyclopentylcarboxylic acid methyl ester (0.20 g, 0.46 mmol) from Step 7 above in MeOH (5 mL) was added aqueous NaOH (1.15 mL of a 2.0 N solution, 2.3 mmol). The mixture was refluxed for 5 days. The mixture was acidified to pH 2 by the addition of 2 N aqueous HCl and the solvent was removed under reduced pressure. The residue was suspended in DMF (5 mL) and to the mixture was added DIEA (0.17 mL, 1.0 mmol) and di-tert-butyldicarbonate (0.10 g, 0.46 mmol) were added and the mixture was stirred at ambient temperature for 14 h. The solvent was removed under reduced pressure and the residue was partitioned between EtOAc (50 mL) and 0.25 M aqueous citric acid (25 mL). The organic phase was washed with water (25 mL), dried (MgSO4), filtered, and the solvent was removed under reduced pressure to give 1-(1-(1-(4-(N-Boc-4-piperidinyloxy)-2-methoxyphenyl)cyclopentylcarboxylic acid as an amorphous solid (HPLC retention time=10.0 min (method A)).

Quelle