Urea → 5-Nitroquinazoline-2,4(1H,3H)-dione

Reaktionsgleichung

[NH2:1][C:2]1[CH:10]=[CH:9][CH:8]=[C:7]([N+:11]([O-:13])=[O:12])[C:3]=1[C:4]([OH:6])=O.[NH2:14][C:15](N)=[O:16]>C(O)(=O)C.O>[N+:11]([C:7]1[CH:8]=[CH:9][CH:10]=[C:2]2[C:3]=1[C:4](=[O:6])[NH:14][C:15](=[O:16])[NH:1]2)([O-:13])=[O:12]

Komponenten

Versuchsvorschrift

A mixture of 2-amino-6-nitro-benzoic acid (60 g, 329 mmol) and urea (257.3 g, 4285 mmol) in acetic acid (1.65 lit.) was heated to reflux for 24 h. The acetic acid was evaporated under reduced pressure and the residue obtained was diluted with water (2.5 lit). The solid product separated out was filtered and washed with water. The product was collected and dried in an air oven to give 44 g of the product as a yellow solid; 1H NMR (δ ppm, DMSO-d6, 300 MHz): 11.58 (br. s, 1H); 11.55 (br.s, 1H); 7.76 (t, J=8.4, 1H); 7.41 (d, J=7.8, 1H); 7.32 (d, J=8.4, 1H).