Reaktionsgleichung
[O:1]=[C:2]1[NH:6][CH:5]([CH2:7][CH2:8][C:9]([OH:11])=O)[CH2:4][CH2:3]1.C(OC(=O)C)(=O)C.CC1OC(C)(C)OC(=O)C=1.C=C1OC(=O)C1>>[CH2:4]1[CH:5]2[N:6]([C:9](=[O:11])[CH2:8][CH2:7]2)[C:2](=[O:1])[CH2:3]1Komponenten
Versuchsvorschrift
In a process for preparing dihydro-1H-pyrrolizine-3,5(2H, 6H)-dione comprising the steps of catalytically hydrogenating an ester of 4-(hydroxyimino)heptanedioic acid and subsequently cyclizing the resulting product to dihydro-1H-pyrrolizine-3,5(2H,6H)-dione, the improvement comprises reacting an alcoholic solution of a mono(lower alkyl) ester of 4-(hydroxyimino)heptanedioic acid, wherein lower alkyl comprises from one to three carbon atoms, with hydrogen gas at a temperature of about 60° C. in the presence of rhodium/alumina catalyst and a tertiary lower alkyl amine, wherein said lower alkyl amine comprises from three to nine carbon atoms, to produce 5-oxo-2-pyrrolidinepropanoic acid; and thereafter heating said 5-oxo-2-pyrrolidinepropanoic acid in the presence of a cyclizing agent selected from acetic anhydride, 2,2,6-trimethyl-1,3-dioxen-4-one, and diketene at a temperature of about 90° C. to produce dihydro-1H-pyrrolizine-3,5(2H,6H)-dione.
Aufarbeitung
- temperatureand thereafter heating
Quellen und Nachweise
- ORD-Eintrag
- ord-a0894d6580a741cba8f872bfbd9b211b
- Quelldatensatz
- uspto-grants-1987_05
- Patentnummer
- US04663464
Verknüpfte Notizen
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