3-Pyridinecarboxaldehyde, 2-amino- → HCID 67388842, compound

Participants

Reaction Conditions

Reaction Steps

A 2-aminopyridine-3-carbaldehyde (650 mg) was added to a stirred solution of methyl 3-amino-2-hydroxy-benzoate (890 mg) in methanol (10 ml) and dichloromethane (5 ml). The resulting solution was stirred at 50° C. for 10 hours. The crude product was purified by flash chromatography on silica gel eluting with 1 to 2% methanol in dichloromethane. The solvent was evaporated to dryness to afford methyl 2-(2-amino-3-pyridyl)-2,3-dihydro-1,3-benzoxazole-7-carboxylate (400 mg) as a pale yellow solid. Manganese(IV) oxide (4629 mg) was added to a solution of this yellow solid (400 mg) in dichloromethane (5 ml) and tetrahydrofuran (10 ml), the mixture was stirred at 25° C. for 15 hours. The mixture was filtered and the filtrate was adsorbed on silica gel and purified by flash chromatography on silica gel eluting with 30 to 50% ethyl acetate in petroleum ether. The solvent was evaporated to dryness to afford methyl 2-(2-amino-3-pyridyl)-1,3-benzoxazole-7-carboxylate (345 mg) as a pale yellow solid. NMR Spectrum: (CDCl3) 4.06 (s, 3H), 6.79 (dd, 1H), 6.89 (bs, 2H), 7.43 (dd, 1H), 7.92 (dd, 1H), 8.00 (dd, 1H), 8.26 (dd, 1H), 8.44 (dd, 1H); Mass spectrum: M+H+ 270;

Provenance & Evidence