Formation and Reactivity of a Mn(O)(μ-O)Ce Species: A Closest Mimic of Photosystem II.

Understanding the basic structure of the oxygen-evolving complex (OEC) in photosystem II (PS-II) and the water oxidation mechanism can aid in the discovery of more efficient and sustainable catalysts for water oxidation. In this context, we present evidence of the formation of a [(TPA)Mn(O)(μ-O)Ce(NO)] () complex (TPA = tris(pyridyl-2-methyl)amine) by adding aqueous ceric ammonium nitrate to an acetonitrile solution of the [(TPA)Mn] () complex. This unique intermediate () was analyzed by using various spectroscopic techniques and electrospray ionization mass spectrometry. Remarkably, closely mimics the structure of Mn(O)(μ-O)Ca(OH) proposed in the OEC of PS-II. Notably, reacts effectively with ferrocene derivatives, indicating that redox-active Ce binding enhances the electron transfer efficiency. Additionally, demonstrated the ability to perform oxygen atom transfer and hydrogen atom abstraction reactions. The discovery of this reactive [(TPA)Mn(O)(μ-O)Ce(NO)] species provides exciting opportunities for investigating the structure of the Mn(O)(μ-O)Ca(OH) unit in the OEC.