Trifluoroacetic acid → 2-(5-Bromo-pyridin-3-yl)-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethyl ester

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Reaction Conditions

Reaction Steps

To a mixture of 2-(5-bromo-pyridin-3-yl)-4-hydroxy-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethyl ester (42.2 g, 100 mmol) and triethylsilane (30 mL) at 25° C. was added trifluoroacetic acid (15 mL) dropwise. The resulting mixture was stirred at 25° C. for 4 h. 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 (2×100 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-(5-bromo-pyridin-3-yl)-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethyl ester (11 g, 28.3%) as a white solid: LC/MS m/e calcd for C19H21BrN2O2 (M+H)+: 390.40, observed: 389.0 & 391.0.

Provenance & Evidence