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The transfer of a hydrogen atom is a crucial step in a wide variety of chemical and biological processes and modus operandi of many metalloenzymes. While several factors that govern the reactivity and selectivity were already clarified in the past century, a growing body of experimental and theoretical studies also revealed numerous gaps in our unified understanding. As a consequence, the direct functionalization of non-activated C-H bonds by synthetic catalysts is still very limited. In the thesis, the hydrogen-atom-abstraction (HAA) reactions are broken down into the elementary proton- and electron-transfer steps and the reactivity/selectivity of oxidants is analyzed with respect to their physico-chemical properties, acidity constants and reduction potentials. First, a quantum chemical (QM)-based computational protocol for calculation of reduction potentials of iron complexes is introduced and validated over a large series of experimental data, including a set of challenging mononuclear FeIV O species that provide direct connection to biomimetic non-heme iron catalysis. Next, the methodology is extended to deal with reduction potentials of transition-metal complexes possessing higher total molecular charges, experimentally measured in polar solvents. In such cases, the accurate description of solvation... |
