Hydrochloric Acid → Methyl 3-amino-5-(4-fluorobenzyl)picolinate

Participants

Reaction Steps

A mixture of methyl 5-[(4-fluorophenyl)methyl]-3-nitro-2-pyridinecarboxylate (200 g, 0.66 mol) and Degussa 10% Pd on carbon (50% by weight water, 20 g) in THF (1.5 L) was stirred under an atmosphere of H2 for 2 d. The mixture was filtered through celite and the filtrate was re-subjected to similar hydrogenation conditions with 10% Pd on carbon (30 g) at 45° C. for 7 d. During this time, conc. HCl (14 mL, 0.17 mol) in MeOH (75 mL) and 10% Pd on carbon (18 g) were added in approximately three portions each. The mixture was filtered through celite, concentrated at reduced pressure, reconstituted in CH2Cl2 and washed with saturated NaHCO3 solution. The organic phase was concentrated and the resulting material was triturated with EtOAc to provide the product as an off-white solid: 1H NMR (CDCl3) δ 7.94 (1H, d, J=1.5 Hz), 7.11 (2H, m), 6.98 (2H, m), 6.72 (1H, 1.5 Hz), 5.67 (2H, br s), 3.95 (3H, s), 3.89 (2H, s); ES+ MS: 261 (M+H+, 100).

Provenance & Evidence