Diazomethane → Methyl 3-aminopyridine-2-carboxylate

Participants

Reaction Steps

3-Aminopicolinic acid (115) (0.585 g, 4.24 mmol) was dissolved in MeOH (absolute, 45 mL). The solution was stirred while an ethereal solution of diazomethane was added until a yellow color persisted (~30 mL). The solution was stirred an additional 30 min, and the solvent rota-evaporated. The resulting residue was dried under reduced pressure at room temperature to yield 0.635 g (98.5%) of crude 116 as a yellow residue. The crude residue was chromatographed on a column of silica (12 g, Mallinckrodt, grade 62, mesh 60-200, used as received) using CHCl3 -MeOH [19:1, (180 mL), 7:3 (100 mL), 1:1 (100 mL), 100% MeOH (150 mL)]. After collecting appropriate fractions, rota-evaporating off the solvent and drying under reduced pressure at 25° C., 0.333 g (51.7%) of 116 was obtained as a yellow solid; mp 139°-146° C.; Rf =0.54 [CHCl3 -MeOH (9:1)]. IR (KBr) 3455, 3295, 3160, 1689, 1617, 1408, 1335, 1244, 1115. 1H NMR (CDCl3) δ3.98 (t, J=7.2, 3, CH3O--), 5.73 (d, J=1.8, 2, NH2), 7.05 (dd, J1 =1.2, J2 =8.4, 1, H-4), 7.22 (dd, J1 =4.2, J2 =8.4, 1, H-5), 8.07 (dd, J1 =1.2, J2 =4.2, 1, H-6).

Provenance & Evidence