Trifluoroacetic acid → 2-(3-Methoxy-phenyl)-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid methyl ester

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Reaction Conditions

Reaction Steps

To a stirred mixture solution of 4-hydroxy-2-(3-methoxy-phenyl)-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid methyl ester (3.4 g, 10.2 mmol) and triethylsilane (6.0 mL) at 25° C. was added trifluoroacetic acid (3.0 mL) dropwise. The resulting mixture solution was stirred at 25° C. for 3 hours. Then the reaction mixture was concentrated in vacuo and the residue was extracted with ethyl acetate (2×200 mL), washed with saturated aqueous sodium bicarbonate solution (4×100 mL), dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was triturated with methanol. The resulting precipitate was collected, dried in vacuo to afford 2-(3-methoxy-phenyl)-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid methyl ester (1.6 g, 50%) as a white solid: LC/MS m/e calcd for C20H23NO3 (M+H)+: 326.41, observed: 326.2.

Provenance & Evidence