Density Functional Theory (DFT) is a powerful tool for treating large organometallic structures efficiently and accurately. DFT calculations on the Hg-catalyzed oxidation of methane to methyl bisulfate in sulfuric acid suggest the lowest energy pathway involves a closed-shell electrophilic C–H activation mechanism coupled with metal alkyl reductive functionalization and oxidation by SO3. Comparison to Tl, Zn, and Cd suggests that Hg is unique in its ability to catalyze this set of reaction steps. Comparison to K2S2O8 highlights the selectivity of this C–H activation reaction as opposed to radical conditions. In contrast, DFT calculations indicate that CoIII(TFA)3 oxidizes methane through a radical TFA ligand decarboxylation pathway. A similar decarboxylation pathway is identified for MnIII(TFA)3, but the low spin ground state of TlIII(TFA)3 favors electrophilic C–H activation over this decarboxylation pathway. DFT calculations indicate that Cp(PPh2Me)Co=CF2 undergoes [2 + 2] cycloaddition with TFE by a unique open-shell singlet diradical mechanism. The significant stability of the perfluorometallacyclobutane reveals why catalytic metathesis with TFE is difficult.
College and Department
Physical and Mathematical Sciences; Chemistry and Biochemistry
BYU ScholarsArchive Citation
Fuller, Jack Terrell, "Computational Studies on Mechanisms and Reactivity of Mercury and Cobalt Organometallic Reactions" (2016). All Theses and Dissertations. 5974.
DFT, mercury, cobalt, C–H activation, decarboxylation, tetrafluoroethylene