Ammonium formate → (4-Fluoro-1-tetrahydropyran-2-yl-benzimidazol-5-yl)methanamine

Participants

Reaction Conditions

Reaction Steps

To a solution of 150 (5.8 g, 0.022 mol) in MeOH (100 mL) was added zinc dust (2.9 g, 0.044 mol) and ammonium formate (2.8 g, 0.044 mol). The resulting mixture was heated to 75° C. for 2 h. The mixture was filtered through a Celite® pad. The filtrate was concentrated and the crude product was purified by SiO2 chromatography eluting with 5% MeOH/DCM to afford 2.6 g (47%) of (4-fluoro-1-tetrahydropyran-2-yl-benzimidazol-5-yl)methanamine (152) as a yellow solid: 1H-NMR (400 MHz, RT, CDCl3): δ 1.66-1.80 (m, 3H), 1.92-1.96 (m, 1H), 2.06-2.14 (m, 2H), 3.68-3.74 (m, 1H), 4.23-4.26 (m, 1H), 4.40 (br, 2H), 5.49-5.52 (dd, 1H), 6.94-6.99 (dd, 1H), 7.18-7.23 (t, 1H), and 7.37-7.39 (d, 1H); MS (ESI) m/z=250.2 [M+1]+.

Provenance & Evidence