10.18453/rosdok_id00005152 El-Sepelgy, Osama Osama El-Sepelgy http://d-nb.info/gnd/1276052901 https://orcid.org/0000-0003-3131-4988 Universität Rostock 2025 540 Chemistry & allied sciences 2025 en https://purl.uni-rostock.de/rosdok/id00005152 urn:nbn:de:gbv:28-rosdok_id00005152-3 This thesis explores biomimetic catalytic systems inspired by metalloenzymes, utilizing ligand-to-metal charge transfer (LMCT) and metal-ligand cooperation (MLC) to enable efficient 3d-metal catalysis. By using earth-abundant metals, these approaches mimic enzymatic mechanisms where ligands actively participate in reactions. It covers cobalt catalysis for visible-light-induced radical desaturation and manganese pincer complexes for various redox transformations. The research integrates experimental and theoretical studies to optimize sustainable catalytic systems.