Trifluoroacetic acid → Methyl 6-(6-methoxy-2-thiophen-3-yl-1H-indol-3-ylmethyl)pyridine-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 6-[2-(2-tert-butoxycarbonylamino-4-methoxyphenyl)-3-oxo-3-thiophen-3-ylpropyl]pyridine-2-carboxylate (2.10 g) in dichloromethane (21 mL) was added dropwise trifluoroacetic acid (4.2 mL) under ice-cooling. This mixture was stirred at 30° C. overnight. The reaction mixture was concentrated under reduced pressure. The residue was dissolved in ethyl acetate, and this solution was washed with a saturated aqueous sodium hydrogen carbonate solution. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate-hexane) to obtain the title compound (938 mg). 1H-NMR (CDCl3) δ ppm: 3.86 (3H, s), 4.05 (3H, s), 4.54 (2H, s), 6.76 (1H, dd, J=2.2, 8.5 Hz), 6.90 (1H, d, J=2.2 Hz), 7.19-7.24 (1H, m), 7.28-7.35 (2H, m), 7.41 (1H, dd, J=3.0, 5.0 Hz), 7.52 (1H, dd, J=1.3, 3.0 Hz), 7.62 (1H, t, J=7.8 Hz), 7.93-7.98 (1H, m), 8.07 (1H, br s).

Provenance & Evidence