Green Selective Oxidation Of Arylboric Acid And Arylalcohol

Phenols and aromatic aldehydes are widely chemical raw materials and have important application value in industry,agriculture,medicine and fine chemical industry.At present,the methods of industrial production of phenols and aromatic aldehydes have many disadvantages,such as long technological process,many by-products,high production cost and serious of environmental pollution.Therefore,it has become research hotspot to develop the preparation methods of phenols and aromatic aldehydes that meet the requirements of green chemistry,such as short process,high atomic utilization,simplicity easy operation,and harmless non-toxic byproducts.Thesis focuses on the selective oxidation of aryl boric acid to phenols and the selective oxidation of aromatic alcohols to aromatic aldehydes.With sodium perborate(SPB)as oxidant,a green reaction system was designed for highly efficient selective oxidation of aryl boric acid to phenolic compounds.The catalytic system possessed high activity,high selectivity as well as the stability.With the sodium perborate as green oxidant and phenyl boric acid can yield 98%,phenol in the green aqueous phase for 5 min without catalyst,and there are no other oxidation by-products.It is found that the green oxidation system can be applied to the highly efficient selective oxidation of aryl boric acid compounds to phenols by the scope of substrates.The thermokinetic of the reaction was studied by using the themogram obtained by microcalorimeter.Combined with the DFT calculation,the reaction mechanism was studied from the aspects of experiment and theory.The green selective oxidation of benzyl alcohol was studied with carbon-based non-metallic catalyst.A series of N and O doped carbon-based catalysts(QAC)were prepared from quinone-amine polymer.With oxygen as the oxidant,the catalyst can realize the efficient green selective oxidation of benzyl alcohol to prepare benzaldehyde.The catalytic reaction system has high activity at room temperature,and its TOF can reach 29.7×10-4 mol·g-1·h-1.The reaction conditions were optimized and the influence of solvent and catalyst on the high activity and high selectivity in water reaction system was discussed.It is found that the green catalytic oxidation system can be applied to the selective oxidation of aryl alcohols,and the method is universal.The possible reaction mechanism was proposed by controlled experiments and the simulated catalyst with small molecule compounds.In addition,the reaction was studied with free radical quencher and EPR spectrum,it was found that the influence of free radical quencher on the reaction yield could not be used to simply determine whether the oxidation reaction was free radical or not.