pH-Responsive, Self-Assembled Ruthenium Nanodrug: Dual Impact on Lysosomes and DNA for Synergistic Chemotherapy and Immunogenic Cell Death.

A NEW LOOK AT MOLECULAR AND ELECTRONIC STRUCTURE OF [Fe2]4+ AMIDINATES: EXPERIMENTAL AND THEORETICAL STUDIES Krzesimir Koronaa, Kornel Sacharczuka, Dawid Pinkowiczb, Adam Kubasc and Janusz Lewińskia,c,* a Faculty of Chemistry, Warsaw University of Technology, Warsaw, Poland b Faculty of Chemistry, Jagiellonian University, 30-387 Cracow, Poland c Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland krzesimirkorona@gmail.com Transition metal complexes incorporating the metal-metal (M-M) bond are a subject of widespread interest, including fundamental curiosity and potential applications in catalysis and small molecules’ activation. The most known M-M bonded compounds are binuclear paddlewheel-type complexes, which generally show strong M-M interactions, leading to a low-spin bimetallic core, often with multiple bonding between metal atoms.[1,2] However, M-M bonded compounds with Fe or Co centres often show a thermally-persistent high-spin ground state, which is interesting from the point of view of molecular magnetism. Herein, I present our studies about M-M interactions in high-spin [Fe2]4+ formamidinates.[3] Particularly, I show how subtle changes in the ligand backbone can dramatically affect the molecular and electronic structure of [Fe2]4+ complexes. Thus, switching from phenyl to p-tolyl N-substituted formamidinate ligand results in a major structure change – the formation of an unprecedented non-centrosymmetric complex [Fe(μ-DTolF)3Fe(κ2-DTolF)] incorporating variously coordinated N,N-bidentate symmetric ligands. Finally, we also provided a new ground state electronic structure of complexes [Fe2(μ-DPhF)4] and [Fe(μ-DTolF)3Fe(κ2-DTolF)], based on high-level abinitio calculations, and supported by magnetic measurements, Mössbauer spectroscopy, and cyclic voltammetry. Moreover, the presented [Fe2]4+ complexes exhibit fieldinduced slow magnetic relaxation with the effective magnetisation reversal barrier. Our studies set the stage for further advances in the fundamental chemistry of M-M bonded complexes and their applications in catalysis and molecular magnetism. _______ [1] Cotton F.A., Murillo C.A., Walton R.A., Multiple Bonds between Metal Atoms, Springer, NY, 2005. [2] Duncan Lyngdoh R.H., Schaefer H.F., King R.B,, Chem. Rev. 2018, 118, 11626–11706. [3] Korona K., Terlecki M., Justyniak I., Magott M., Żukrowski J., Kornowicz A., Pinkowicz D., Kubas A., Lewiński J., Chem. Eur. J., 2022, 28, DOI: 10.1002/chem.202200620.