A laccase–mediator system based on caffeic acid for the synthesis of benzimidazoles

In this study, a laccase-mediator system utilizing caffeic acid as a mediator was developed for the green synthesis of benzimidazole derivatives. The reactions were carried out under mild conditions at room temperature, using citrate buffer as the reaction medium and aerial oxygen as the oxidant. Caffeic acid effectively mediated electron transfer between the enzyme and substrates, significantly enhancing reaction yields. Different benzimidazole derivatives were synthesized with good to excellent yields (54-93%) without the use of toxic chemicals. The results highlight the efficiency, environmental compatibility, and synthetic potential of this laccase-mediator system approach in organic synthesis.