Study On New Oxidation Mode And Polymerization Reaction Of Phenanthrene Derivatives

Polycyclic aromatic hydrocarbons phenanthrene is one of the important research objects in the field of comprehensive utilization of coal resources.9-Phenanthrenol is an important derivative of phenanthrene.Its selective oxidation can be used to prepare chiral ligands or phenanthrene-9,10-dione(PQ)and other chemicals with higher application value.It is widely used in organic synthetic chemistry,Materials chemistry and medicinal chemistry and other fields.The oxidation strategies of9-Phenanthrenol reported in the literature include dehydrogenative coupling reaction and C-10 oxygenation.Further development of the strategy of regioselective oxidation of 9-phenanthrenol can provide novel compounds with structural innovations,which in turn expands the application fields of phenanthrene and expands its application value.This article mainly explores the non-classical oxidation strategy of 9-phenanthrenol.In the first part,a new reaction model for the conversion of9-phenanthrenol into phenanthrenyl ketal and 9-fluorenone is introduced.In the second part,a new synthetic method of degradable polyphenanthrenyl ketal polymer is developed using the new oxidation mode of 9-phenanthrenol.1.Using 9-phenanthrenol as a substrate,reacting with a base at 80°C and oxygen to obtain 9-fluorenone with a yield of 90%.To expand the substrate scope,the reaction has the characteristics of good functional group tolerance and mild reaction conditions.Through the study of the mechanism,a phenanthrenyl ketal structure was discovered,which can be obtained from 9-phenanthrenol by controlling the amount of base and can be quantitatively converted into 9-fluorenone.Therefore,we identified phenanthrenyl ketal as an intermediate in the reaction.2.Using 3-br-9-Phenanthrenol as substrate,under 80?,N₂conditions,using THF and Na₂CO₃solution as solvent,Pd(PPh₃)₄as catalyst,and reacting with symmetric dihalogenated aromatic hydrocarbons,The high-molecular-weight monomers were obtained in medium to good yields.This type of monomer structure undergoes polymerization under alkaline conditions and in an oxygen atmosphere to obtain polyphenanthrene ketal polymers with a high yield.The product can be degraded into small molecules of fluorenone and carboxylic acid.The polymerized product is passed through nuclear magnetism,MALDI-TOF and other characterization confirm the structure.Through the above research,we have transformed toxic and environmentally harmful polycyclic aromatic hydrocarbons into useful structural units or functional materials.And discovered an unprecedented phenanthrene ketal structure,which is very meaningful.