Electronic property of alkoxo-bridged tetranuclear Fe(II) cluster and CO2 hydrogenation reactivity

Here we report on the synthesis of tetranuclear Fe(II) cluster [Fe4I2(O2C14H11)(6)] (1) derived from a benzoin-based scaffold. The Fe centers displayed a rhombus-like core structure, including two types of coordination environments: trigonal bipyramid and trigonal prism. The binding energy of the trigonal prismatic Fe(II) 2p electron appeared similar to 1.43 eV higher than that of the trigonal bipyramidal Fe(II) 2p electron because of more Fe-O bonds. The trigonal bipyramidal Fe site exhibited stoichiometric CO2 hydrogenation reactivity with the assistance of an external Lewis basic agent.