Solvent Coordination Strength: An Essential Factor for Metal Catalytic Reactions

Abstract

Open metal sites in metal-organic frameworks (MOFs), typically occupied by the coordination bonding of Lewis-base solvent molecules used in MOF synthesis, often play a crucial role in various catalytic reactions. In this talk, we introduce the ability of chloromethanes to form weak coordination bonding, which can provide the activation state to metal centers for catalytic reactions. More concretely, while the possible metal coordination of chloromethanes (dichloromethane and trichloromethane) has rarely been known, we show that the neutral chlorine atom in such chloromethanes can have a weak coordination bonding at metal centers, and this weak coordination can exchange relatively stronger coordination of Lewis-base molecules such as water, methanol, ethanol, and other catalytic substrates. Exploiting this weak coordination bonding, we demonstrate that the coordination exchangeability of the weak coordination bonding makes the metal center continuously activated, and thus, it substantially enhances the catalytic activity of the metal centers.