Reaktion #7481

Reaktionsgleichung

sodium hydroxide

4-[(4-ethylphenyl)methyl]-5-methyl-3-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyloxy)-1H-pyrazole

cesium carbonate

benzyl(2-bromoethyl)ether

→

1-(2-benzyloxyethyl)-4-[(4-ethylphenyl)methyl]-3-(β-D-glucopyranosyloxy)-5-methyl-1H-pyrazole

Lösungsmittel

methanol

acetonitrile

Water

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling to room temperature
2. 2
   workup.WAITthe reaction mixture was further stirred overnight
3. 3
   workup.STIRRINGthe mixture was stirred at room temperature for 1 hour
4. 4
   workup.DISTILLATIONthe mixture was purified by CBA solid phase extraction (washing solvent: distilled water, eluent: methanol)
5. 5
   Sonstigesuccessively by column chromatography on silica gel (eluent: dichloromethane/methanol=10/1-5/1) to give

Vorschrift

To a suspension of 4-[(4-ethylphenyl)methyl]-5-methyl-3-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyloxy)-1H-pyrazole (0.030 g) and cesium carbonate (0.091 g) in acetonitrile (0.4 mL) was added benzyl(2-bromoethyl)ether (0.035 mL), and the mixture was stirred at 80° C. for 30 minutes. After cooling to room temperature, the reaction mixture was further stirred overnight. To the reaction mixture were added methanol (0.4 mL) and 2 mol/L aqueous sodium hydroxide solution (0.55 mL), and the mixture was stirred at room temperature for 1 hour. Water was added to the reaction mixture, and the mixture was purified by CBA solid phase extraction (washing solvent: distilled water, eluent: methanol), and successively by column chromatography on silica gel (eluent: dichloromethane/methanol=10/1-5/1) to give to give 1-(2-benzyloxyethyl)-4-[(4-ethylphenyl)methyl]-3-(β-D-glucopyranosyloxy)-5-methyl-1H-pyrazole (0.012 g).

Quelle