Construction Of Ionic Liquid Microemulsion And Its Application In The Field Of Selenium Catalysis

Selenium had been discovered over full 200 years.Given a relatively large atom radius and existence of empty 4d orbits that can form bond,Selenium atom tends to form covalent bonds with relatively low bond energy,which enables selenium contained compounds possess a unique oxidation reduction performance and anti-oxidation resistance.Most recently,due to these properties,Selenium contained compounds have be used as highly efficient catalysts for organic synthesis.Microemulsions consist of surfactant,co-surfactants,oil and water,which are thermodynamically stable systems.Microemulsion could significantly improve the collision probability of the two incompatible reactants,and therefore enhance the reaction rate and conversion.This paper firstly investigated the micellization of the mixtures of amphiphilic imidazole ionic liquids with different molecular structures and non-ionic surfactant Triton X-114 in aqueous solutions,and then study the phase transition and structures of the microemulsions stabilized by those surfactant mixtures,and finally a novel synthesized diselenide((RSe)2)was introduced to the stable microemulsion to represent as a catalyst,and then the effect of the structure and composition of microemulsions on the catalysis efficiency for the oxidation of?-Ionone was systematically investigated.The main researches are as follows:1,Conductivity,fluorescence,1H NMR and light scattering were applied to systematically investigate the critical micelle concentration,interaction parameters,the location of ionic liquids in the Triton X-114 micelles,and the size and Zeta potential of the complexes for the surfactant mixtures of imidazole ionic liquids as single-tailed[C8mim]Br,two-tailed[C8C8im]Br2 and Gemini[CsC2Csim]Br2 and Triton X.The results showed that the stability of the complex and the strength of the interactions between C8ILs and Triton X-114 were followed as[C8C8sim]Br>[C8C2C8im]Br2>[C8mim]Br.2,Methods of conductivity and rheology were used to study the phase behavior of system of Triton X-114/C8ILs/n-C4H94H/n-C7Hi6/H2O and to investigate the phase transition from water-in-oil to bicontinuous and to oil-in-water.The results revealed that the addition of C8ILs inhibited the transition of cosurfactnat n-C4H9OH from oil phase to the interface layer between oil and aqueous phase,and this effect was followed as[C8mim]Br>[C8C2C8im]Br2>[C8C8im]2Br.3,Oxidative stimulus response of dioctyl diselenide in aqueous solutions were firstly investigated,and then the diselenide was introduced into Triton X-114/C8ILs/n-C4H9OH/n-C7H16/H2O microemulsions to investigate effect of the structure and composition of the microemulsions to the catalyst efficiency of the diselenide to Baeyer-Villiger oxidation of?-Ionone.It was found that the structure and composition of the microemulsions could significant affect the catalyst efficiency.Inter alia,the microemulsions with bicontinuous structure showed the highest improvement,and the yield reached 92%when the ionic liquid[C8C2C8im]Br2 or[C8C8im]2Br was added.