A Study On The Hydrogen Abstraction Reaction Of Benzene Propylene Promoted By TEMPO

Recently,nitroxides have been focused much attention in oxidation reactions.Among them,TEMPO-like nitroxides are the most widely used and the most representative one which are stable in both thermodynamics and kinetics and can be stable in presence of water and air.However,their free radical activity is relatively low.Thus,TEMPO is usually oxidized to TEMPO + in situ for the oxidation of alcohol compounds.On the other hand,chemists have found that some chemical bonds can be functionalized by TEMPO in the way of hydrogen abstraction.This is a non-metallic catalytic oxidation system which can meet the development of green chemistry.However,to date,TEMPO used for C-H bond oxidation by hydrogen abstraction is rare.This work is mainly based on a study on the hydrogen abstraction reaction of benzene propylene promoted by TEMPO,so as to realize the oxidation of C-H bond.The main works were as following:(1)Hydrogen abstraction reaction of allylbenzene was investigated in the presence of TEMPO.The effects of temperature,solvent,reaction time and additives on the reaction were studied.Cinnamaldehyde was obtained in the yield of 10%-65%.The effect of the substituent on the aryl group was analyzed.It was found that the electronic effect of the substituents on the reaction was not obvious,but the steric hindrance had a certain effect on the reaction.(2)O-aminoallyl benzene was prepared.The resulting aldehyde group can directly react with the amino group to generate quinoline.The reaction was studied in the presence of TEMPO and 4-acetylamino-TEMPO respectively.The effects of solvent and reaction time were discussed and quinoline was obtained in the yield of 23%-63%.It was found that the electronic effect of the substituents on the aryl group was not obvious.