A metal–organic framework-supported dinuclear iron catalyst for hydroboration of carbonyl compounds

Abstract

Preparation of catalytically active dinuclear transition metal complexes with an open coordination sphere is a challenging task because the metal sites tend to be “saturated” with excess donor atoms around during synthesis. By isolating the binding scaffolds with the metal–organic framework (MOF) skeleton and installing metal sites through post-synthetic modification, we succeed in constructing a MOF-supported metal catalyst, namely FICN-7-Fe₂, with dinuclear Fe₂ sites. FICN-7-Fe₂ effectively catalyses the hydroboration of a broad range of ketone, aldehyde, and imine substrates with a low loading of 0.05 mol%. Remarkably, kinetic measurements showed that FICN-7-Fe₂ is 15 times more active than its mononuclear counterpart FICN-7-Fe₁, indicating that cooperative substrate activation on the two Fe centres significantly enhances the catalysis.