[(S)-1-(6-fluoro-1-pyridin-3-yl-1H-benzoimidazol-2-yl)ethyl]carbamic acid tert-butyl ester → (S)-1-(6-Fluoro-1-pyridin-3-yl-1H-benzoimidazol-2-yl)ethylamine

Participants

Reaction Steps

A solution of [(S)-1-(6-fluoro-1-pyridin-3-yl-1H-benzoimidazol-2-yl)ethyl]carbamic acid tert-butyl ester (292 mg, 0.82 mmol) in TFA (4 mL) and DCM (12 mL) was stirred for 1 h at RT. The reaction mixture was loaded onto an Isolute® SCX-2 cartridge. The cartridge was washed with MeOH, followed by 2M NH3/MeOH. The basic fractions were combined and concentrated in vacuo. The resulting residue was purified by column chromatography (Si—PPC, gradient 0-10% 2M NH3 in MeOH/DCM) to afford the title compound as a pale yellow oil (141 mg, 67%). Marfey's test: 76% de. LCMS (Method C): RT 1.34 min [M+H]+ 257. 1H NMR (CDCl3, 400 MHz): δ 8.80 (1H, dd, J=5.0, 1.5 Hz), 8.73-8.72 (1H, m), 7.81 (1H, ddd, J=8.0, 2.5, 1.5 Hz), 7.71 (1H, ddd, J=9.0, 4.5, 0.5 Hz), 7.56 (1H, ddd, J=8.0, 5.0, 1.0 Hz), 7.04 (1H, ddd, J=9.5, 9.0, 2.5 Hz), 6.75 (1H, ddd, J=8.5, 2.5, 0.5 Hz), 4.08 (1H, q, 6.5 Hz), 1.87 (2H, bs), 1.48 (3H, d, J=6.5 Hz).

Provenance & Evidence