Formamidine acetate → 5,7-dimethoxyquinazolin-4(3H)-one
Reaction equation
[NH2:1][C:2]1[CH:11]=[C:10]([O:12][CH3:13])[CH:9]=[C:8]([O:14][CH3:15])[C:3]=1[C:4](OC)=[O:5].C(O)(=O)C.[CH:20](N)=[NH:21]>COCCO>[CH3:15][O:14][C:8]1[CH:9]=[C:10]([O:12][CH3:13])[CH:11]=[C:2]2[C:3]=1[C:4](=[O:5])[NH:21][CH:20]=[N:1]2Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 130 °C
Procedure
A mixture of methyl 2-amino-4,6-dimethoxybenzoate (6.46 g, 30.6 mmol), formamidine acetate (15.92 g, 153 mmol) in 2-methoxyethanol (50 mL) was heated at 130° C. for 4 hours. After the solvent was removed under reduced pressure, the reaction was quenched with water, filtered, washed with water, and dried under vacuum with P2O5 to afford 5,7-dimethoxyquinazolin-4(3H)-one as a solid (4.805 g, 76%). 1H NMR (300 MHz, DMSO-d6) δ 11.7 (br, 1H), 7.98 (s, 1H), 6.72 (d, 1H), 6.60 (d, 1H), 3.92 (s, 3H), 3.88 (s, 3H); LC-MS (ESI) m/z 207 (M+H)+.