Strategies for Synthesis of Imidazo[1,2-a]pyridine Derivatives: Carbene Transformations or C-H Functionalizations.

The imidazo[1,2-a]pyridines are an important target in organic synthetic chemistry and have attracted critical attention of chemists mainly due to the discovery of the interesting properties exhibited by a great number of imidazo[1,2-a]pyridine derivatives. Although lots of synthetic methods of imidazo[1,2-a]pyridines have been developed in the past years, the chemistry community faces continuing challenges to use green reagents, maximize atom economy and enrich the functional group diversity of product. Undoubtedly, with its low cost and lack of environmentally hazardous byproducts, cascade reactions and C-H functionalizations are ideal strategies for this field. In this record we highlight some of our progress toward the goal to synthesis of imidazo[1,2-a]pyridine derivatives through carbene transformations or C-H functionalizations.