p-Toluenesulfonic acid → 1H-Benzimidazole-2-pentanamine

Participants

Reaction Steps

A mixture of 678 g (6 mols) of caprolactam, 865 g (8 mols) of o-phenylene diamine and 60 g of p-toluene sulphonic acid is melted in a nitrogen atmosphere, 108 g of water distilling off over a period of 6 hours at an internal temperature of 200° to 250°C. The reaction mixture is then subjected to fractional distillation under reduced pressure, giving 1003 g (82.4 % of the theoretical) of 2-(5'-aminopentyl)- benzimidazole with boiling point of 210° to 215°C at 0.05 Torr, and a melting point of 101°C.

Provenance & Evidence