Sulfuric Acid → HCID 178517235, compound

Reaction equation

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

Participants

Procedure

To a mixture of 147 mg (0.616 mmol) of 5,7-dichloro-2,4-quinolinediol and 126 mg (1.82 mmol) of NaNO2 in 3 mL of 0.2N NaOH in ice-bath was added dropwise 2 mL of aqueous 2N H2SO4. The mixture was stirred in ice-bath for 4 h after addition of H2SO4, filtered and dried to leave an orange solid. The solid was crystallized by boiling with 10 mL of ethanol (95% ). The solution was cooled to room temperature, filtered and dried to leave 132 mg (83%) of 5,7-dichloro-3-oximequinoline-2,4-dione as a yellow solid, mp 244°-245° C. (decomposed). 1H NMR (CDCl3 +DMSO-d6), 7.011 (d, 0.44, J=1.8) 7.080 (m, 1.54), 11.567 (sb, 0.35), 11.821 (s, 0.46). MS, 258 (100, M+), 241 (60), 214 (80), 187 (20), 160 (30). High resolution MS, Calcd for C9H435Cl2N2O3, 257.9595, found 257.9598.