Water → 2-(3-Bromo-phenyl)-6-fluoro-4-hydroxy-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-8-carboxylic acid methyl ester

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Reaction Conditions

Reaction Steps

To a mixture of 2-{[1-(3-bromo-phenyl)-methylidene]-amino}-5-fluoro-benzoic acid methyl ester (50 g, 59.8 mmol) and ytterbium(III) triflate hydrate (3.7 g, 5.95 mmol) in dry tetrahydrofuran (30 mL) at 25° C. was added isobutyraldehyde (4.3 g, 59.5 mmol) and water (1.1 mL, 59.5 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 (2×100 mL), washed with brine, dried over anhydrous sodium sulfate and concentrated in vacuo to afford 2-(3-bromo-phenyl)-6-fluoro-4-hydroxy-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-8-carboxylic acid methyl ester (24.3 g, 100%) as a light yellow oil: LC/MS m/e calcd for C19H19BrFNO3 M+: 408.3, observed: 408.1.

Provenance & Evidence