Salicylaldehyde → cis-5-(Methoxycarbonyl)piperidine-2-carboxylic Acid
Reaktionsgleichung
[NH:1]1[CH2:6][C@H:5]([C:7]([O:9][CH3:10])=[O:8])[CH2:4][CH2:3][C@@H:2]1[C:11]([O:13]C)=[O:12].C(=O)C1C(=CC=CC=1)O>C(O)(=O)C>[CH3:10][O:9][C:7]([C@H:5]1[CH2:6][NH:1][C@@H:2]([C:11]([OH:13])=[O:12])[CH2:3][CH2:4]1)=[O:8]Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Reaktionsbedingungen
- Temperatur
- 100 °C
Versuchsvorschrift
Dimethyl cis-piperidine-2,5-dicarboxylate (112 g, 0.56 mol), 5 salicylaldehyde (3 ml, 0.056 mol) and glacial acetic acid (600 ml) were combined and the resulting mixture heated at about 100° C. for 60 hours. The mixture was cooled, than stripped in vacuo to a thick oil from which 61.7 g (59%) of title products crystallized upon stirring with 800 ml of isopropyl alcohol. Product ratio was determined by 1H-NMR (D2O, 300 MHz), a peak at 3.13 ppm (t, 1H, J=14.5 Hz) being diagnostic of trans, and a peak at 3.33 ppm (dd, 1H) being diagnostic of cis.