Executive Summary : | Transition-metal-catalyzed C-H functionalization of aromatic rings has been extensively studied for the past two decades due to its ability to replace inert hydrogen with various substituents, including reactive functional groups. Traditional methods involve using aryl halides or pseudohalides as reactants, which can generate side products and require laborious purification processes. Researchers believe that C-H functionalization could be a solution for sustainable development, leading to the development of new strategies for functionalizing inert C-H bonds using transitionmetal-catalysts. The challenge in C-H functionalization is regio-selective incorporation of the substituent, which can be addressed by introducing directing groups in the arene. These groups bind to transition-metal-catalysts and selectively deliver the catalyst to a proximal C-H bond. However, sulfur tethered directing groups have rarely been employed in C-H functionalization reactions, possibly due to strong chelation of sulfur, which can poison many transition-metal catalysts. The importance of aryl sulfides in C-H thiolation reactions is highlighted, and the synthetic versatility of sulfur tethered directing group sulfoxide is explored to derive functionalized organo sulfur compounds of biological interest. Additionally, S,S-coordinated Pd-complexes are prepared and studied for their catalytic application in cross-coupling reactions. |