C3-methylation of imidazopyridines via C(sp2)-H activation using magnetic Cu-MOF, and DMSO as solvent and Methyl source.

In this study, we introduce a protocol for the methylation of the C-H bond at the C position in imidazo[1,2-a]pyridine scaffolds, employing magnetic def./Cu-MOF for the activation of C(sp2)-H bonds. The term 'def' refers to strategically induced defects in the Metal-Organic Framework (MOF), which are designed to improve its catalytic efficiency. These defects are generated using specific agents, with benzoic acid serving as the defect-promoting agent, leading to controlled structural imperfections within the MOF. This approach offers an efficient and reliable method for the methylation of imidazopyridines, showcasing excellent compatibility with various functional groups, high site selectivity, and outstanding product yields. Additionally, dimethyl sulfoxide acts as both the solvent and the source of methyl groups in the reaction, further streamlining the process.