Reaction Steps
To a solution of tert-butyl 4-((8-(4-oxo-4,5,6,7-tetrahydro-1H-pyrrolo[3,2-c]pyridin-2-yl)quinolin-2-yl)oxy)piperidine-1-carboxylate (0.103 g, 0.22 mmol) in DCM (3.0 mL) at 0° C. was added TFA (0.5 mL, 6.73 mmol). The reaction was stirred at 0° C. for 1 h, then at RT for 40 min. The reaction mixture was then concentrated, the residue was dissolved in DCM, washed with a saturated aq. solution of NaHCO3, dried over MgSO4, filtered and concentrated. The residue was dissolved in DMSO (2.0 mL) and purified by rpHPLC (Silicycle Silichrome XT C18 column; 30×150 mm, 5 μm, 5-95% 0.1% TFA/ACN in 0.1% TFA/water by volume over 10 min.), then dried in a Genevac Series II Evaporator to afford 2-(2-(piperidin-4-yloxy)quinolin-8-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one 2,2,2-trifluoroacetate (48.7 mg, 0.094 mmol, 32.4% yield) as an amorphous orange solid: 1H NMR (400 MHz, DMSO-d6) δ ppm 11.64 (br. s., 1H), 8.67 (br. s., 1H), 8.47 (br. s., 1H), 8.30 (d, J=9.0 Hz, 1H), 7.96 (d, J=7.2 Hz, 1H), 7.76 (d, J=8.2 Hz, 1H), 7.48 (t, J=7.8 Hz, 1H), 7.35 (d, J=2.0 Hz, 1H), 7.08 (d, J=8.8 Hz, 1H), 6.95 (br. s., 1H), 5.37-5.48 (m, 1H), 3.34-3.50 (m, 4H), 3.18-3.31 (m, 2H), 2.88 (t, J=6.8 Hz, 2H), 2.36 (d, J=14.3 Hz, 2H), 1.87-2.02 (m, 2H). 19F NMR (376 MHz, DMSO-d6) δ ppm −74.36 (s, 3F). m/z (ESI, +ve ion) 363.0 (M+H)+.
