Water → 2-(5-Fluoro-2-methyl-phenyl)-4-hydroxy-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethylester

Participants

Reaction Conditions

Reaction Steps

To a mixture of 4-{[1-(5-fluoro-2-methyl-phenyl)-methylidene]-amino}-benzoic acid ethyl ester (3.01 g, 10.6 mmol) and ytterbium(III) triflate hydrate (0.66 g, 1.06 mmol) in dry tetrahydrofuran (10 mL) at 25° C. was added isobutyraldehyde (0.96 mL, 10.6 mmol) and water (190 mg, 10.6 mmol) dropwise. The reaction mixture was stirred at 25° C. for 5 h. Then the reaction mixture was concentrated in vacuo and the residue was extracted with ethyl acetate (2×50 mL), washed with brine, dried over anhydrous sodium sulfate and concentrated in vacuo to afford 2-(5-fluoro-2-methyl-phenyl)-4-hydroxy-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethylester (3.78 g, 100%) as a light yellow oil: LC/MS m/e calcd for C21H24FNO3 M+: 357.4, observed: 340.3.

Provenance & Evidence