Redox-switchable and metallaphotoredox catalysts based on NDI/PDI-NHC complexes

Abstract

The research presented in this doctoral thesis focuses on the preparation of novel metal complexes bearing a naphthalene-diimide (NDI) or perylene-diimide (PDI) fragment connected to an N-heterocyclic carbene (NHC) ligand. Au(I), Rh(I) and Ir(I)-based catalysts were developed. Given the presence of NDI or PDI in their structure, voltammetric studies revealed that these compounds exhibited two fully reversible reduction waves at relatively accessible potentials, allowing the generation of three different species. These species were characterized by means of spectroelectrochemical studies using infrared and UV-Vis spectroscopy, which demonstrated their stability under the reaction conditions and showed that the reduction of NDI or PDI led to an increase in the electron density of the metal center. These properties were exploited to use these compounds as redox-switchable and metallaphotoredox catalysts.