Hydrochloric Acid → HCID 11380767, compound

Participants

Reaction Steps

Ethyl 6-chloro-8-methyl-2-(trifluoromethyl)-1,2-dihydroquinoline-3-carboxylate (4.5, 0.51 mmol) was suspended in methanol-tetrahydrofuran-water (50 mL, 7:2:1). Lithium hydroxide (1.70 g, 42.3 mmol) was added, and the mixture was gently heated to reflux for two hours. The reaction was cooled to room temperature and 1 N aqueous hydrochloric acid added until pH=1. The organic solvent was removed in vauco to afford a suspension of a crude yellow solid. Diethyl ether (200 mL) was added, and the solution was washed with water (2×200 mL), saturated ammonium sulfate (2×200 mL), dried over sodium sulfate and filtered. The filtrate was concentrated in vacuo to yield 6-chloro-8-methyl-2-(trifluoromethyl)-1,2-dihydroquinoline-3-carboxylic acid (3.8 g, 13.4 mmol) as a yellow solid (95% yield). (CDCl3, 300 MHz) 7.56 (s, 1H), 6.93 (s, 1H), 6.90 (s, 1H), 5.11 (q, 1H, J=7.2 Hz), 4.78 (bs, 1H), 2.08 (s, 3H). HRMS m/z 291.0286(M+, C12H9ClF3NO2, calcd 291.0274).

Provenance & Evidence