Multinuclear late transition metal catalysts for olefin polymerization

Abstract The aim of designing multinuclear catalysts for olefin polymerization is to have the best control on the catalyst behavior and final polymer properties. This control is in relation to superior catalyst activity and selectivity. For these purposes, researches are still trying to pose the active centers in an effective distance to achieve a cooperative effect. Based on this, length and nature of the linker (bridge) play a key role in the adjacency of metal centers and cooperative interactions, consequently. On the other side, late transition metal catalysts (LTMs) as a stunning group of polymerization catalysts due to their structural and behavioral attractions multiply the interests into the multinuclear catalysts. Herein, recent progress in designing the multinuclear LTM catalysts for polymerization of olefins is reviewed. In addition to metal atoms (Co, Fe, Ni and Pd) and diversity of centers (homometallic and heterometallic), the catalyst structures were categorized based on the nature of the bridges including flexible and flexible/rigid bridged, and rigid bridged catalysts. Moreover, a comparison between the multinuclear catalysts and corresponding mononuclears were highlighted along with the mechanism of cooperative effect.