Thionyl Chloride → Methyl 4-chlorocinnoline-3-carboxylate
Reaction equation
S(Cl)([Cl:3])=O.O[C:6]1[C:15]2[C:10](=[CH:11][CH:12]=[CH:13][CH:14]=2)[N:9]=[N:8][C:7]=1[C:16]([O:18][CH3:19])=[O:17]>>[Cl:3][C:6]1[C:15]2[C:10](=[CH:11][CH:12]=[CH:13][CH:14]=2)[N:9]=[N:8][C:7]=1[C:16]([O:18][CH3:19])=[O:17]Participants
3
Procedure
Thionyl chloride (8.15 g, 5 ml) was added dropwise under inert atmosphere to methyl 4-hydroxycinnoline-3-carboxylate (0.50 g, 2.45 mmol). The mixture was heated to reflux for 1.5 h, cooled to room temperature and excess thionyl chloride was removed under vacuum. Toluene (5 ml) was added to the residue. The mixture was stirred at room temperature overnight. The solids were collected by filtration and dried under vacuum. The title compound was isolated as a brown solid (248 mg, 1.11 mmol, 45%). LCMS: m/z 223 [M+H]+.
Workup
- temperatureThe mixture was heated
- temperatureto reflux for 1.5 h
- customexcess thionyl chloride was removed under vacuum
- additionToluene (5 ml) was added to the residue