Electrochemical Cross-Dehydrogenative Coupling Of Isochroman And Ketones And Paired Electrolysis Of Benzyl Methyl Ether With 1,4-Dicyanobenzene

Green chemistry aims to achieve sustainable development by reducing or eliminating the production of environmentally harmful substances in chemical manufacturing and applications.As one of the important means of green chemistry,organic electrosynthesis has become a research field of concern.Dehydrogenative coupling reactions mediated by electrochemistry have the advantage of being green and efficient,and can achieve mild and sustainable reaction conditions.In this paper,the cross dehydrogenation coupling reactions of Isochroman and unactivated ketones were realized by means of electrosynthesis for the first time.Secondly,an attempt was made to synthesize arylbenzyl alcohol by paired electrolysisbenzyl of methyl ether with1,2-dicyanobenzene.In the first chapter of this paper,the development process of electrosynthesis and the principles and advantages of organic electrochemistry were brief introduced,the cross-dehydrogenation coupling reaction and paired electrolysis were reviewed,the main reaction types and recent research results were introduced,and their applications and prospects in organic electrosynthesis were discussed.In the second chapter of this paper,the cross-dehydrogenative coupling reaction between isochroman and unactivated ketones mediated by electrochemistry was studied.The oxonium ions formed by electrooxidation of isochroman were then coupled with nucleophiles to achieve high efficiency synthesis of α-substituted isochroman derivatives.After optimizing the reaction solvent,solvent volume,electrolyte,additive,electrode material,current and reaction time,we determined the optimal reaction conditions.Subsequently,the scope of substrate was explored,and 29 α-substituted isochroman derivatives were obtained in good yields.In the study of the mechanism,we first carried out a series of free radical trapping experiments,and proved that the free radical was the key intermediate of the reaction.The cyclic voltammetry experiments confirmed that Isochroman was firstly oxidized at the anode to form onium ions which then coupled with the nucleophile.This method is characterized by simple operation,mild conditions and no need of exogenous oxidants and transition metal catalysts.It provides an effective way for constructing α-substituted isochroman derivatives.In the third chapter of this paper,the synthesis of aryl benzyl alcohol compounds through the paired electrolysis method of benzyl methyl ether and para-phenylenedinitrile was studied.Aryl benzyl alcohol compounds were synthesized in a one-pot reaction using benzyl methyl ether and para-phenylenedinitrile as model substrates.The optimal reaction conditions were determined by screening the solvent,electrode material,additive,electrolyte,and current.The mechanism of the reaction was proposed based on experiments.This method has the advantages of low-cost raw materials,green methodology,high atom economy,and controllability.