Veratraldehyde → 2-(2-Pyridyl)-3-(3,4-dimethoxy-phenyl)-2-propenenitrile
Reaktionsgleichung
[CH3:1][O:2][C:3]1[CH:4]=[C:5]([CH:8]=[CH:9][C:10]=1[O:11][CH3:12])[CH:6]=O.[N:13]1[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=1[CH2:19][C:20]#[N:21]>C(O)C.N1CCCCC1>[N:13]1[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=1[C:19](=[CH:6][C:5]1[CH:8]=[CH:9][C:10]([O:11][CH3:12])=[C:3]([O:2][CH3:1])[CH:4]=1)[C:20]#[N:21]Komponenten
5
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 2
Versuchsvorschrift
To a stirred solution of 2.0 g (12.0 mmole) 3,4-dimethoxybenzaldehyde in 75 ml absolute ethanol are added 1.56 g (13.3 mmole) 2-pyridylacetonitrile and 12 drops piperidine. The reaction flask is equipped with a condenser and a drying tube (using anhydrous CaSO4), and the reaction is stirred and heated. After refluxing for 6 hours, the reaction is allowed to cool to room temperature and stirred overnight for 16 hours. The solvent is removed by rotary evaporation, and the residue purified by flash chromatography on silica gel, eluting with hexane-ethyl acetate, 4:1. The yellow solid is recrystallized from acetone-hexane to give 2-(2-pyridyl)-3-(3,4-dimethoxy-phenyl)-2-ProPenenitrile, m.p. 112 °-114° C.