Methanol → Methyl 6-nitro-4-oxo-3,4-dihydroquinazoline-8-carboxylate

Reaktionsgleichung

[N+:1]([C:4]1[CH:5]=[C:6]2[C:11](=[C:12]([C:14]([OH:16])=[O:15])[CH:13]=1)[N:10]=[CH:9][NH:8][C:7]2=[O:17])([O-:3])=[O:2].S(=O)(=O)(O)O.[OH-].[Na+].[CH3:25]O>>[N+:1]([C:4]1[CH:5]=[C:6]2[C:11](=[C:12]([C:14]([O:16][CH3:25])=[O:15])[CH:13]=1)[N:10]=[CH:9][NH:8][C:7]2=[O:17])([O-:3])=[O:2]

Komponenten

Edukt 4

HCID 887Methanol

HCID 1118Sulfuric Acid

HCID 14798Sodium Hydroxide

HCID 1362782956-Nitro-4-oxo-3,4-dihydroquinazoline-8-carboxylic acid

Produkt 1

HCID 136278294Methyl 6-nitro-4-oxo-3,4-dihydroquinazoline-8-carboxylateAusbeute 84 %

Versuchsvorschrift

6-nitro-4-oxo-3,4-dihydroquinazoline-8-carboxylic acid (500 mg, 2.13 mmol) was treated with a solution of sulfuric acid ((1.2 equiv.) in anhydrous MeOH (10 mL) under refluxing overnight. After cooling to rt, 2N NaOH solution was added to the reaction mixture to adjust pH˜8. After removal of MeOH, methyl ester was collected by filtration, and washing with water and as yellow solid in 84% yield. 1HNMR (in DMSO): 3.91 (s, 3H), 8.38 (s, 1H), 8.74 (d, J=2.6 Hz, 1H), 8.88 (d, J=2.6 Hz, 1H). Mass: M+H+: 250.