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

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.

1. concentrationThen the reaction mixture was concentrated in vacuo
2. extractionthe residue was extracted with ethyl acetate (2×200 mL)
3. washwashed with saturated aqueous sodium bicarbonate solution (2×100 mL)
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated in vacuo
6. customThe residue was triturated with methanol
7. customThe resulting precipitate was collected
8. customdried in vacuo

ORDレコード

ord-c05de21cff774303b2480424646549fa

出典データセット

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08344137B2