Acetic Acid → 5-Chloro-1,2,3,4-tetrahydroquinoline

Reaction equation

[Cl:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]2[C:3]=1[CH2:4][CH2:5][C:6](=O)[NH:7]2.[BH4-].[Na+].C(O)(=O)C>O1CCOCC1>[Cl:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]2[C:3]=1[CH2:4][CH2:5][CH2:6][NH:7]2

Participants

Procedure

42.5 g of 5-chloro-3,4-dihydrocarbostyril was suspended in 250 ml of dioxane and 44.3 g of NaBH4 was added to the suspension. Then 67 ml of acetic acid (d=1.05) was added dropwise to the mixture at room temperature. After heat-refluxing the resulting mixture for 2 hours the solvent was removed under reduced pressure. Water was added to the residue and insoluble materials were removed by filtration followed by washing with diethyl ether. The residue was extracted with diethyl ether, dried over anhydrous sodium sulfate and distilled under reduced pressure to obtain 36.0 g of 5-chloro-1,2,3,4-tetrahydroquinoline having a boiling point of 116° to 120° C./0.2 mmHg.