Sodium Hydroxide → (2S,4R)-4-hydroxy-1-(4-nitrobenzyloxycarbonyl)-2-[2-(4-nitrobenzyloxycarbonylamino)ethyloxymethyl]pyrrolidine

To a solution of (2S,4R)-2-(2-aminoethyloxymethyl)-4-hydroxy-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (1.12 g) in a mixture of water (20 ml) and tetrahydrofuran (40 ml) was added a solution of 4-nitrobenzyloxycarbonyl chloride (0.85 g) in tetrahydrofuran (4 ml) under ice-cooling with stirring, keeping the pH between 8.5-9.5 with 4N aqueous sodium hydroxide. The mixture was stirred at the same condition for 2 hours. The reaction mixture was evaporated under reduced pressure and then ethyl acetate (50 ml) was added thereto. The organic layer was dried over magnesium sulfate and concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (20 g) and eluted with a mixture of methanol and chloroform (2:98 V/V) to give (2S,4R)-4-hydroxy-1-(4-nitrobenzyloxycarbonyl)-2-[2-(4-nitrobenzyloxycarbonylamino)ethyloxymethyl]pyrrolidine (0.88 g).

1. temperaturecooling
2. stirringThe mixture was stirred at the same condition for 2 hours
3. customThe reaction mixture was evaporated under reduced pressure
4. additionethyl acetate (50 ml) was added
5. dry with materialThe organic layer was dried over magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customto give a syrup
8. washeluted with a mixture of methanol and chloroform (2:98 V/V)

ORD-Eintrag

ord-8ef5dd20c2bc43c1af41ac8d01b3fe6c

Quelldatensatz

uspto-grants-1990_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04963543