Hydrochloric Acid → 6-Chloro-1,2-dihydro-1-methyl-2-(trifluoromethyl)-3-quinoline-carboxylic acid
Reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[N:8]([CH3:12])[CH:7]([C:13]([F:16])([F:15])[F:14])[C:6]([C:17]([O:19]CC)=[O:18])=[CH:5]2.[OH-].[Li+].Cl.C(OCC)C>CO.O1CCCC1.O>[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[N:8]([CH3:12])[CH:7]([C:13]([F:16])([F:14])[F:15])[C:6]([C:17]([OH:19])=[O:18])=[CH:5]2Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Procedure
Ethyl 6-chloro-1,2-dihydro-1-methyl-2-(trifluoro-methyl)-3-quinolinecarboxylate(1.21 g, 3.78 mmol) was suspended in methanol-tetrahydrofuran-water (20 mL, 7:2:1). Lithium hydroxide (0.262 g, 6.24 mmol) was added, and the mixture was gently heated to reflux for two hours. The reaction was cooled to room temperature and 1 N HCl added until pH=1. The organic solvent was removed in vauco to afford a suspension of crude yellow solid. Diethyl ether (20 mL) was added, and the resulting solution was washed with water (2×20 mL), saturated ammonium chloride (2×20 mL), dried over sodium sulfate and filtered. The filtrate was concentrated in vacuo to afford the product as a yellow solid, 6-chloro-1,2-dihydro-1-methyl-2-(trifluoromethyl)-3-quinoline-carboxylic acid. (1.08 g, 98% yield): mp 208-209° C. 1H NMR (CD3OD/300 MHz) 7.69 (d, 1H, J=2.5 Hz), 7.28-7.24 (m, 2H), 6.73 (dd, 1H, J=9.5, 2.5 Hz), 5.13 (q, 1H, J=7.0), 3.16 (s, 3H). Anal. Calc'd for C12H9F3NO2Cl: C, 49.42; H, 3.11; N, 4.80; Cl, 12.16. Found: C, 49.88; H, 3.29; N, 4.59; Cl, 12.42.
Workup
- temperaturethe mixture was gently heated
- temperatureto reflux for two hours
- customThe organic solvent was removed in vauco
- customto afford
- additiona suspension of crude yellow solid
- washthe resulting solution was washed with water (2×20 mL), saturated ammonium chloride (2×20 mL)
- dry with materialdried over sodium sulfate
- filtrationfiltered
- concentrationThe filtrate was concentrated in vacuo
Sources & evidence
- ORD record
- ord-0d2e550634b04be88c8b27b89966e3b0
- Source dataset
- uspto-grants-2001_08
- Patent number
- US06271253B1
Reaction notes
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