反应详情

温度

25 °C

To a stirred mixture solution of 4-[(3-bromo-benzylidene)-amino]-3-chloro-benzoic acid methyl ester (39.8 g, 113.2 mmol) and ytterbium(III) triflate hydrate (10.5 g, 16.9 mmol) in dry tetrahydrofuran (100 mL) at 25° C. was added isobutyraldehyde (10.4 mL, 113.2 mmol) and water (2.1 mL, 113.2 mmol) dropwise. The reaction mixture was stirred at 25° C. for 16 h. Then the reaction mixture was concentrated in vacuo and the residue was extracted with ethyl acetate (2×200 mL), washed with brine, dried over anhydrous sodium sulfate and concentrated in vacuo to afford 2-(3-bromo-phenyl)-8-chloro-4-hydroxy-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid methyl ester (48 g, quant.) as a light yellow oil which was used for next step without further purification: LC/MS m/e calcd for C19H19BrClNO3 (M+H)+: 425.73, observed: 405.9 & 407.9.

1. concentrationThen the reaction mixture was concentrated in vacuo
2. extractionthe residue was extracted with ethyl acetate (2×200 mL)
3. washwashed with brine
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated in vacuo