Trifluoroacetic acid → 2-(3-Bromo-5-(piperidin-4-ylidenemethyl)phenoxy)-5-(trifluoromethyl)pyridine

To a solution of tert-butyl 4-(3-bromo-5-(5-(trifluoromethyl)pyridin-2-yloxy)benzylidene)piperidine-1-carboxylate (1.2 g, 2.33 mmol) in CH2Cl2 (5 mL) was added trifluoroacetic acid (1.79 mL, 23.37 mmol) at 0° C. The reaction mixture was stirred for 30 min at 0° C. and at RT for 1 h. The reaction mixture was quenched with saturated aqueous NaHCO3 and extracted with CH2Cl2 three times. The organic layer was washed with brine, dried over Na2SO4, and evaporated to dryness to give the title compound (1.15 g, 100%). 1H NMR (500 MHz, CDCl3): δ 8.43 (s, 1H), 7.93 (d, J=6.75 Hz, 1H), 7.23 (s, 1H), 7.20 (s, 1H), 7.05 (d, J=8.45 Hz, 1H), 6.89 (s, 1H), 6.39 (s, 1H), 3.23 (m, 2H), 3.12 (m, 2H), 2.75 (m, 2H), 2.64 (m, 2H); m/z (413.2, 415.2, M+ H+).