Synthesis Of Polymeric Manganese Porphyrin And High-Efficiency Aerobic Catalytic Oxidation Of Cyclic Ketones And The Degradation Of Hydroquinone

In recent years,metalloporphyrins caused widespread attentions on account of their various catalytic activities.They have been generally applied to the catalytic oxidations of cyclic ketone,alcohol and hydrocarbon.However,the single metal porphyrins are easy to degrade and self oxidize in the process of catalytic oxidation,and they are difficult to recycle.It has become a new research trend to polymerize single metal porphyrin into conjugated porous metalloporphyrin polymers which have better stability and excellent catalytic performance by bridge chain.There are many kinds of conjugated porous metalloporphyrin polymers.This paper innovatively uses CuI/N and N-dimethyglycine as catalyst systems to synthesize four phenyl amino manganese porphyrin polymer,and it was used in the catalytic oxidation of ketones and the catalytic degradation of hydroquinone,which showed excellent catalytic performance.Firstly,four（4-nitro phenyl）porphyrin（TNPP）,the precursor of manganese manganese porphyrin,was synthesized by Alder method,then TNPP was restored to four（4-amino phenyl）porphyrin（TAPP）by SnCl2 in the acid environment.With that,we gained the（4-amino）manganese porphyrin（T（p-NH₂）PPMnCl）by the reaction of MnCl₂·4H₂O with TAPP.Furthermore,the metalloporphyrin polymer was synthesized by the Suzuki coupling of T（p-NH₂）PPMnCl and p-dibromobenzene,which used Cul/N,N-dimethyglycine as catalyst.In this paper,the reaction temperature、time、solvent、alkali and reactant proportion have been researched.We find the optimum condition:11℃,N2 protection,K₂CO₃ and T（p-NH₂）PPMnCl:p-dibromobenzene（1:2.5）were added in the dioxane solvent,reacting for 24h,and the yield was as high as 97%.The pore size distribution data indicated that the polymer pore size was mainly concentrated at 1,29 nm,and the total volume was 0,214 cm³g^-1.The microporous volume was 0.093 cm³g^-1 accounting for 43.6%of the total volume.Electron microscopic analysis showed that the polymer had a good mesh and pore structure.Secondly,the metalloporphyrin polymer,which was synthesized under the optimum conditions,was applied to the catalytic oxidation of cyclic ketones.The reaction conditions such as the reaction temperature,the ratio of cyclic ketones and adjuvant,the reaction time and the amount of catalyst input during the catalytic oxidation were studied.The result showed that the yield of caprolactone was more than 97%at 60 ℃for 5h under the conditions of cyclohexanone as reaction substrate and 1,2-dichloroethane as solvent and benzaldehyde as catalytic oxidative adjuvant.GC-MS and GC test indicated that almost no by-products were produced.The catalyzer which was used in the catalytic oxidation of other cyclic ketones showed certain catalytic effect.Furthermore,the study of catalyst recycling showed that the it could still show high activity and good stability after repeated use,and it was easy to recycle and reuse.Finally,based on the work of the first two parts,we further investigated the application of metalloporphyrin polymer in the oxidation degradation of organic pollutants hydroquinone.The result showed that the degradation rate of hydroquinone in the solution was 97.13%under the condition of simulated sunlight,oxygen and acidic environment（pH=6）,catalytic degradation for 5 hours.In addition,the capture agents of various active substances were added into the catalytic degradation system,and the mechanism of catalytic degradation was investigated.