Formic Acid → 1-Methyl-1H-benzimidazole-5-carboxylic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of 3-amino-4-(methylamino)benzoic acid (9 g, 1.0 eq) in 50 mL water, was added 50 mL formic acid and heated at 85° C. overnight. The mixture was cooled, concentrated in vacuo, and dissolved in water. Then 2N HCl was added to adjust pH to 1-3. The suspension was filtered and washed with water to give the product (9.7 g, 84%). 1H NMR (400 MHz, DMSO-d6) δ 9.48 (s, 1H), 8.37 (s, 1H), 8.12 (d, J=8.8 Hz, 1H), 8.00 (d, J=8.8 Hz, 1H), 4.06 (s, 3H).

Herkunft & Nachweise