A rapid and efficient one-pot method for the synthesis of 2-(N-substituted)-aminobenzimidazoles is described. The reaction is promoted by dithiocarbamate and catalytic CuO. This procedure is general and can be applied to synthesize many potential drug candidates.
BOP efficiently promoted the phosphonium-mediated cyclization of thioureas, leading to a convenient synthesis of 2-aminobenzimidazoles. Compared to conventional methods, the reactions were complete at room temperature with times ranging from a few minutes to 1 h in near quantitative yields. This method is also applicable to the synthesis of more challenging structures such as 2-akylaminobenzimidazoles