Green approaches for the synthesis of poly-functionalized imidazole derivatives: A comprehensive review

The naturally occurring five-member imidazole derivatives have shown interesting biological as well as physiochemical properties and consequently they have found several chemicals, optical, pharmaceutical, and other useful biological applications. The interesting biological properties and wide applications of poly-functionalized imidazole molecules attract researchers to develop novel strategies for the synthesis of poly-functionalized imidazole moieties. As a result, several research articles have been published in the literature. In this review article, we have disclosed various applications as well as the traditional and modern green approaches for the synthesis of imidazole derivatives including conventional synthesis, microwave-assisted synthesis, ultrasound promoted synthesis, and synthesis under green catalyst or a without catalyst. The most of the traditional methods of imidazole synthesis, there is no requirement of high pressure, energy, temperature, or toxic chemicals. However, the modern methods are accomplished through catalyst- and solvent-free conditions with high purity and excellent yields of the products. In this review, we have provided the examples of reactions for the synthesis of imidazole derivatives which fulfill all the essential criteria required to achieve the green and sustainable chemistry.