Application Of Electrochemistry-Mass Spectrometry In Electrochemical Oxidation Reaction

Compared with traditional organic chemistry,electrochemical synthesis has more and more attention because of its advantages of green,atomic economy,mild reaction conditions,and short process flow.Mass spectrometry(MS)is a type of fast and efficient analytical technique that is commonly used for the identification of the structure of reaction intermediates and products.Electrochemical-mass spectrometry(EC-MS)integrates the advantages of electrochemical technology and mass spectrometry,and is widely used in the research of proteomics and drug metabolism.In this paper,the electrochemical oxidation of proton pump inhibitors(PPIs)precursors and N,N-dialkylaniline was studied using EC-MS technology,which expanded the application range of EC-MS technology in electrochemical reactions.The main contents of this thesis are as follows:(1)Application of EC-MS technology to study the electrochemical oxidation process of proton pump inhibitors(PPIs)precursors.Proton pump inhibitors(PPIs)are commonly used anti-ulcer drugs in clinic,but there are few reports about the electrochemical synthesis of such drugs.We synthesized 6 kinds of PPIs sulfide precursors and measured their oxidation potential through cyclic voltammetry experiments;based on the oxidation potentials obtained from cyclic voltammetry experiments,the electrical properties of PPIs sulfide precursors were studied online using EC-MS Chemical oxidation reaction and online structure identification of oxidation products using tandem mass spectrometry;found that there are two possible electrochemical oxidation pathways for PPIs sulfide precursors,and the site selectivity of oxidation depends on the aromatic ring of PPIs sulfide precursors The electronic effect of the substituent.(2)Application of EC-MS technology to study the electrochemical oxidation coupling reaction of N,N-dialkylarylamine.Benzidine derivatives are an important class of organic intermediates.Thetraditional preparation method is mainly obtained through the oxidative coupling reaction of aromatic amines,which requires to use chemical equivalents of oxidants.In order to avoid the use of oxidation reagents,we studied the electrochemical oxidation coupling reaction of N,N-dialkylarylamine.The conditions of N,N-dialkylarylamine electrochemical oxidation coupling reaction were optimized online using EC-MS technology,and the oxidation yield was estimated according to the signal intensity of the mass spectrum of the product before and after the reaction.Under the chemical reaction conditions,the results of EC-MS experiments were verified,and the applicable scope and law of the reaction were explored.Nine benzidine derivatives were synthesized;the above-mentioned electrochemical coupling reaction mechanism was speculated.The above experiments show that the electrochemical-mass spectrometry(EC-MS)combined technology can realize the online simulation experiment of electrochemical redox reaction,which has the advantages of sensitivity,rapidness,accurate and reliable results,etc.EC-MS has important application value in the study of electrochemical synthesis and reaction mechanism.