Reaction Steps
(R)-tert-Butyl 4-((1-(3,5-dibromo-1H-indazol-7-yl)ethoxy)methyl)-4-(4-fluorophenyl)piperidine-1-carboxylate (99 mg, 0.16 mmol) was dissolved in trifluoroacetic acid (20% in dichloromethane, 6 mL) and stirred for 30 min. The reaction was concentated and the resulting residue loaded onto a strong cation exchange cartridge in methanol. The cartridge was washed with several volumes of methanol which were discarded. The product was eluted with 2M ammonia in methanol and concentrated to give 82 mg (94%) as a foam solid. 1H-NMR (CDCl3, 500 MHz) δ 7.62 (d, J=1.5 Hz, 1H), 7.25 (dd, J=9.5, 5.8 Hz, 2H), 7.12 (d, J=1.5 Hz, 1H), 7.03 (dd, J=8.6, 8.6 Hz, 2H), 4.46 (q, J=6.7 Hz, 1H), 3.44 (s, 2H), 3.36 (d, J=8.9 Hz, 1H), 3.24 (d, J=9.2 Hz, 1H), 2.87 (m, 2H), 2.68 (m, 2H), 2.14 (m, 1H), 2.03 (m, 1H), 1.84 (m, 2H), 1.41 (d, J=6.4 Hz, 3H); 13C NMR (126 MHz, CDCl3) δ ppm 161.5 (d, J=246 Hz), 139.3, 137.3, 128.7, 128.61, 128.57, 127.7, 125.3, 121.7, 121.6, 115.6, 115.5, 114.3, 79.0, 77.8, 50.5, 42.5, 42.4, 41.4, 33.7, 33.4, 22.1.
