Reversible Grafting in Surface Organometallic Chemistry with a Late Transition‐Metal Amidinate Precursor

Abstract

Supported catalysts are central to industrial catalytic processes. While traditional synthesis methods often yield poorly defined materials, thus complicating structural elucidation, Surface Organometallic Chemistry (SOMC) offers a solution, producing well‐defined structures. Recent advances in SOMC precursor development have shown that amidinate‐based precursors are a privileged class of precursors to generate supported metallic nanoparticles. In that context, this study investigates the grafting mechanism of a prototypical amidinate precursor, Ir(COD)(DIA) (1‐Ir), onto SiO2. Unique to amidinate complexes, grafting is shown to occur without ligand release, creating a reversible covalent bond. Using Ir‐TBOS as a molecular analogue, the structure of the grafted species and the reversibility of the reaction with O‐H groups are demonstrated using IR spectroscopy, single X‐Ray diffraction, variable‐temperature NMR spectroscopy, X‐Ray absorption spectroscopy (XAS), and supported by DFT calculations. Notably, we show that a partial degrafting is also possible at elevated temperatures under vacuum