The Catalytic Application Of KI In The Eletrophilic Substitutional Selenenylation Of Anilines

In this dissertation,we report the eletrophilic substitutional selenenylation of anilines catalyzed by KI and the alkoxylselenenylation of alkenes promoted by p-toluenesulfonic acid.This dissertation mainly includes three parts:1.Literature review.This chapter introduces the development of organoselenium compounds and their synthetic methods,the application of electrophilic selenium,nucleophilic selenium,organic selenium compounds as catalyst in organic synthesis.The selenium-containing medicial compounds are also briefly introduced.2.The catalytic application of KI in the eletrophilic substitutional selenenylation of anilines.Due to the known methods for the preparation of arylselanyl anilines usually use toxic and expensive regents,we have investigated the novel KI catalyzed selenenylation of anilines.In the presence of a catalytic amount of KI combined with oxidant H2O2,a convenient catalytic procedure has been developed for the direct preparation of arylselanyl anilines from N,N-disubstituted anilines and diselenides with high regioselectivity and good yield via an electrophilic substitution.A proposed catalytic mechanism for the selenation of N,N-disubstituted aniline is hypothesized.3.The alkoxylselenenylation of alkenes promoted by p-toluenesulfonic acid.In the presence of p-toluenesulfonic acid,the reaction of alkenes with diselenides and oxidant mchloroperbenzoic acid proceeds efficiently in alcohols at room temperature,producing a series of corresponding 2-alkoxy-1-selenenyl compounds with high regioselectivity and good yields.The reaction conditions are optimized and a plausible mechanism for the acid promotion is suggested: firstly,a rapid cleavage of Se-Se bond by the reaction of oxidant of mCPBA,diselenide form the the electrophilic selenium species,which then reacts with alkene to produce the unstable cyclic intermediate,after a solvolysis of it in alcohol,the desired product is obtained.