1,3-Dimethoxybenzene → 5-Methoxy-2-thioxodihydropyrimidine-4,6(1H,5H)-dione
Reaktionsgleichung
[CH3:1][O:2]C1C=CC=C(OC)C=1.COC1C=CC2C(=CC(OC)=CC=2)C=1.[NH:25]1[C:32](=[O:33])[CH2:31][C:29](=[O:30])[NH:28][C:26]1=[S:27]>>[CH3:1][O:2][CH:31]1[C:29](=[O:30])[NH:28][C:26](=[S:27])[NH:25][C:32]1=[O:33]Komponenten
4
Versuchsvorschrift
The Birch reduction products of 1,3-dimethoxybenzene and of 2,7-dimethoxynaphthalene each react with thiobarbituric acid to form the conjugated methoxy-thiobarbituric acid dyes as shown in FIG. 13. For this reaction, no solvent is used. The reactants were melted at 145° C. for 15 min. Methanol condensing at the walls of the flask showed successful reaction. Purification was carried out by simple filtration over a short column of SiO2 with CH2Cl2. Yields were typically around 60%.