Synthesis of Novel Unsymmetric Bisbenzimidazoles

Using chloroacetic acid, p‐hydroxyl aromatic aldehydes 1 and aromatic diamines 3 as starting materials, novel bisbenzimidazoles 5 with unsymmetric structure were synthesized via aryloxyacetic acid intermediates 2 . Four new intermediates 4 and ten target molecules 5 were characterized by FTIR, ¹H NMR, ¹³C NMR, MS and elemental analysis. Different synthetic methods, including one‐pot synthesis and intermittent microwave promotion, were investigated. The research provides a new method and idea for the synthesis of bisbenzimidazoles.