N,N-Dimethylaniline → 4-Chlorobenzo[g]quinoline
Reaction equation
[N:1]1[C:10]2[C:5](=[CH:6][C:7]3[CH:14]=[CH:13][CH:12]=[CH:11][C:8]=3[CH:9]=2)[C:4](O)=[CH:3][CH:2]=1.CN(C)C1C=CC=CC=1.P(Cl)(Cl)([Cl:27])=O>>[Cl:27][C:4]1[C:5]2[C:10](=[CH:9][C:8]3[CH:11]=[CH:12][CH:13]=[CH:14][C:7]=3[CH:6]=2)[N:1]=[CH:2][CH:3]=1Participants
4
Procedure
Under a nitrogen atmosphere, benzo[g]quinolin-4-ol (6) (100 mg, 0.51 mmol) was refluxed in 2 ml of phosphorus oxychloride (0.25 M) in the presence of N,N-dimethylaniline (0.25 mL, 3.8 equivalents) until deemed complete by TLC. Removal of the excess phosphorus oxycloride in vacuo and flash chromatography (gradient: 9:1 to 8:2 to 7:3 hexanes:EtOAc) afforded 108 mg of clean 4-chlorobenzo[g]quinoline (7b) in quantitative yield.
Workup
- customRemoval of the excess phosphorus oxycloride in vacuo and flash chromatography (gradient: 9:1 to 8:2 to 7:3 hexanes:EtOAc)