Synthesis of Benzimidazole-Substituted Arylboronic Acids via Aerobic Oxidation of 1,2-Arylenediamines and Formyl-Substituted Aryl MIDA Boronates using Potassium Iodide as a Catalyst

A highly efficient protocol for the synthesis of benzimidazole-substituted arylboronic acids was developed via aerobic oxidative cyclization of 1,2-aryldiamines and formyl-substituted aryl MIDA (N-methyliminodiacetic acid) boronates using potassium iodide as a nucleophilic catalyst. Furthermore, a one-pot protocol for the synthesis of benzimidazole-substituted arylboronic acids from 1,2-phenylenediamines and formyl-substituted arylboronic acids was developed without the isolation of any intermediates. The resulting boronic acids were further subjected to Suzuki-Miyaura coupling reactions without isolation, leading to diaryl-substituted benzimidazoles with only one separation step.