Phosphorus oxychloride → 4,6-Dichloro-3-nitroquinoline
Reaktionsgleichung
[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[N:8]=[CH:7][C:6]([N+:12]([O-:14])=[O:13])=[C:5]2O.O=P(Cl)(Cl)[Cl:18]>>[Cl:18][C:5]1[C:4]2[C:9](=[CH:10][CH:11]=[C:2]([Cl:1])[CH:3]=2)[N:8]=[CH:7][C:6]=1[N+:12]([O-:14])=[O:13]Komponenten
3
Versuchsvorschrift
11 g (48.97 mmol) 6-chloro-3-nitro-quinolin-4-ol (Example 23b) in 80 ml POCl3 are heated and kept under reflux for 5 h (tlc-control). The cool reaction mixture is poured slowly into 1.5 l ice-water. The title compound separates as a solid. The mixture is stirred for 15 min. the temperature not exceeding 0-5° C. The solid is filtered off, washed with water and dissolved in 200 ml ethylacetate. The organic phase is washed with a mixture of 200 ml water and 38 ml 2N sodium hydroxide solution and again water. After drying over MgSO4, the solvent is evaporated almost to dryness; to the residue hexane is added and the product is isolated by filtration as a dark-grey powder. This material is used in the next step without further purification. mp: 118-120° C.; NMR (DMSO-d6): 9.43/s (1H); 8.43/d (1H), 8.25/d (1H), 8.10/d×d (1H); HPLC: tret=12.84 min (Grad 1).