Triphenylphosphine → ethyl 5-{(2RS,3RS)-3-amino-2-(4-nitrophenyl)butyl}-2-furancarboxylate

3.66 g of ethyl 5-{(2RS,3SR)-3-hydroxy-2-(4-nitrophenyl)butyl}-2-furancarboxylate in 40 ml of tetrahydrofuran was mixed with 4.32 g of triphenylphosphine, 2.60 ml of diethyl azodicarboxylate and 4.53 g of diphenylphosphoryl azide under cooling with ice under stirring and stirred at room temperature for 18 hours. The reaction solution was evaporated to dryness under reduced pressure, and the residue was purified by silica gel column chromatography [hexane/ethyl acetate=50/1→30/1]. The resulting azide was refluxed together with 2.37 g of triphenylphosphine in 55 ml of 10% hydrous tetrahydrofuran under heating for 6 hours. The reaction solution was cooled to room temperature, and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography [ethylene chloride/methanol=100/1→20/1] to give 2.89 g of the title compound as a yellow oily substance.

1. temperatureunder cooling with ice
2. stirringstirred at room temperature for 18 hours
3. customThe reaction solution was evaporated to dryness under reduced pressure
4. customthe residue was purified by silica gel column chromatography [hexane/ethyl acetate=50/1→30/1]
5. temperatureThe resulting azide was refluxed together with 2.37 g of triphenylphosphine in 55 ml of 10% hydrous tetrahydrofuran
6. temperatureunder heating for 6 hours
7. distillationthe solvent was distilled off under reduced pressure
8. customThe residue was purified by silica gel column chromatography [ethylene chloride/methanol=100/1→20/1]

ORD-Eintrag

ord-e15ff9b65b464e289f0cb9f647275f87

Quelldatensatz

uspto-grants-1999_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05981573