Theoretical Study On The Catalytic Oxidation Mechanism Of Benzopyrene By Manganese Azacorrole And Its Regulation By External Electric Fiel

First,the catalytic oxidation mechanism of benzo（a）pyrene by manganese corrolazine and the regulation of the reaction by oriented external electric fields were systematically investigated using DFT calculations.DFT calculations showed that in the absence of an electric field,a total of three steps（epoxidation,hydrogen transfer and rearrangement）were required if[Mn]-O-O corrolazine wants to oxidize benzo（a）pyrene to hydroxyl species.The first step produces the carcinogenic epoxy-Ba P with a reaction potential barrier of 17.6 kcal/mol.The second step of epoxy-Ba P was converted to the second intermediate with a reaction potential barrier of 46.2 kcal/mol.The third step is the continued conversion of the intermediate to hydroxy-Ba P with a reaction potential barrier of 58.0 kcal/mol.The higher reaction potential in the latter two steps would make the reaction easily stay in the epoxy-Ba P.This shows that the oxidation of benzo（a）pyrene to hydroxyl species by[Mn]-O-O corrolazine is very difficult without the involvement of electric fields.However,the application of oriented external electric fields changes the interaction between the dipole moment and electric fields.The increase or decrease of ionicity in the direction of the"reaction axis"stabilizes different transition states.These new transition states have a significant impact on the reaction mechanism.Among them,the appearance of the transition state TS1_Hgreatly facilitates and changes the reaction course,allowing a direct"one-step"detoxification of benzo（a）pyrene at a suitable reaction potential.In addition,the role of the electric field and its selectivity for the transition state were discussed in the F_Z3direction as an example.Regardless of the presence or absence of electric fields,the reaction ends with the production of highly valent active species Mn（V）-oxo corrolazine.Second,practical technical difficulty of applying a directionally oriented external electric fields was then considered,and the possibility of using the addition of anions in the system as an approximate substitute for the selective effect of electric fields on the reaction was investigated.That is,the effect of oriented external electric fields was replaced by an internal electrostatic catalytic strategy.The effect of the addition of anions and cations on the reaction was studied in three regions and the different effects of the anions and cations were compared.The similarities and differences between this method and the applied electric field were compared by means of the reaction mechanism,reaction potential barrier,and electron density difference verified by IRC.A brief analysis of the mode of action of different anions and cations was presented.It was confirmed by extensive calculations that the modulating effect of electric field on the reaction can be approximated by the addition of anions and cations as a substitute.Finally,other studies during the master’s degree were summarized,one being the theoretical study of functionalized cobalt corroles as catalysts for OER/ORR reactions.Functionalized cobalt corrole complexes have demonstrated their potential as non-precious metal catalysts for OER/ORR reactions and provided a theoretical basis for further design and development of mono-or bi-functional catalysts for OER or ORR reactions.Secondly,the theoretical study of axial ligands in modulation of the rebound reaction have confirmed that the rebound reaction can be slowed down by axial ligands,and the mechanism of the rebound reaction has been investigated in depth.This work is expected to guide the development of related metal-oxygen complexes.It provides a theoretical model for a deeper understanding of the rebound reaction and a theoretical basis for replicating the enzyme catalysis in an artificial system.