Synthesis,Structure And Bromination Catalytic Kinetics Of Functional Vanadium Complexes

Oxidative bromination reaction of organic compound is a kind of common reaction in the organic synthesis.The organic bromide products applied to each field of industrial production,using as an important intermediate or material the synthetic drugs,pesticides,flavors,fuel,explosives and fire agent of organic products.The conventional bromination reaction usually uses the electrophilic substitution reaction,and the bromine source was bromine,N-bromobutanimide(NBS)etc.However,in the process of the reaction,the utilization ratio of bromine was low,only about 50%.Not only the atom economy was poor,and the selectivity of the reaction was not high,most of all,but the main product contained corrosive HBr that will cause serious pollution to the environment,which has violated the trend of the development of modern green chemistry.Therefore,we focused on searching for a safe and pollution-free oxidant and efficient catalyst.Vanadium/Oxovanadium Complexes we synthesis were simulated with the nature vanadium haloperoxidase(V-HPOs)which have catalytic activity.Structurally,the center vanadium atom was coordinated by nitrogen atoms and oxygen atoms of organic heterocyclic ligands,forming a similar structure to V-HPOs.Through a lot of experiments we can conclude that the model complexes we synthesized also have high catalytic activity.The structural characters of the seven complexes were determined by single crystal X-ray diffraction,descripting the structures and the complicated intermolecular hydrogen bonding of the complexes in detail.The complexes were characterized by IR spectrum,UV spectrum,thermo gravimetric analysis and X-ray powder diffraction.Then,we measured the catalytic activity of the complexes,and summed up with the relationship between the structure and catalytic activity of the complexes according to the experimental results.Furthermore,we explored the catalytic bromination reaction and applied it in the detection of hydrogen peroxide,obtaining the minimum detectable concentration of hydrogen peroxide.