反应详情

温度

50 °C

To 3-amino-4-(2-cyano-ethylamino)-benzoic acid methyl ester (4.0 g) was added formic acid (25 ml) and the mixture heated to 50° C. for 3 h. It was then concentrated and the residue recrystallised from EtOAc to afford 4.0 g (95%) of 1-(2-cyanoethyl)-1H-benzimidazole-5-carboxylic acid methyl ester. MS-ESI m/z 230 (M+1); 1H NMR (300 MHz, CDCl3) δ 2.95 (t, 2H), 4.0 (s, 3H), 4.55 (t, 2H), 7.4 (d, 1H), 8.1 (m, 1H), 8.15 (s, 1H), 8.55 (s, 1H)

1. concentrationIt was then concentrated
2. customthe residue recrystallised from EtOAc