| Task specific ionic liquids (TSILs) are attracting enormous interest due to the possibilities to modulate their physicochemical properties through an appropriate structure modification or component change and to tailor the best ionic liquid for each specific application. Intelligent choice of the anion and cation or the introduction of functional groups on cations and (or) anions of the ionic liquids can create a TSILs that has wide anodic or cathodic limits (or both), a more hydrophobic or less hydrophobic behavior, acid and/or base property, etc. Ecological and economic concerns associated with the chemical synthesis have posed stringent and compelling demands for greener, more sustainable technologies. Obviously, in developments of the various oxidation processes, fine-tuning the reactivity of common oxidants, expanding the application of 'new' oxidants, avoiding the use of conventional volatile solvents, application of solvent-free reaction and recycling reaction media are of prime importance to reduce dramatically energy, matter costs, wastes and risks. It should greatly enhance the interest of industry in oxidation chemistry.To take demends of chemical industry into account, we have designed and prepared twelve novel oxidizing task-specific ionic liquids and investigated the special oxidation reactions in other seven task-specific ionic liquids. Details are as follows:1. Four novel ionic liquids based on peroxydisulfate are designed and synthesized: 1-methyl-3-butylimidazolium peroxydisulfate, 1-methyl-3-hexylimidazolium peroxydi-sulfate, 1-methyl-3-octylimidazolium peroxydisulfate, 1-methyl-3-decylimidazolium peroxydisulfate. Their composition and structures have been confirmed by FT-IR, 1H NMR and element analysis. Their melting point, density, conductivity, viscosity, electrochemical window, thermal stability and solubility have been also investigated. Some alcohols and thiols are oxidized with relatively high conversion and yield, using these TSILs as solvents and reagents, which indicate the good prospects of application of TSILs in the oxidation reactions.2. Four ionic liquids based on alkyl-imidazolium or alkyl-pyridinium cation and periodate anion have been first prepared:1-methyl-3-octylimidazolium periodate, 1-hexyl-pyridinium periodate,1-octyl-pyridinium periodate,1-decylpyridinium periodate. They have been characterized by FT-IR,1H NMR, XRD and element analysis and their composition and structures have been confirmed. Their melting point, density, conductivity, electrochemical window, thermal stability and solubility have been studied. Without any other solvents and catalysis, alcohols are oxidized with relatively high conversion and yield using these TSILs as solvents and reagents. It shows bright potential of the ionic liquids in Green Chemistry. 3. Trihalide task-specific ionic liquids are synthesized with halogen and halide ionic liquids for the application of nucleophilic substitution reaction of aromatic compounds, chlorination reaction of some organic compounds and quantitative determination of chloride ion. A series of work is described as follows. (1) The ionic liquid containing [Cl-Br2]- is applied to nucleophilic substitution reaction of aromatic compounds and the products are obtained with high selectivity. The influence of different ionic liquids, different aromatic compounds, the amounts of bromine and reaction time are discussed and the reaction mechanism is proposed to explain the reaction process. (2) The ionic liquid containing [Cl-Cl2]- is applied to the chlorination reaction of some organic compounds, such as alkenes, arenes, ketones. Reaction process is rather simple with high yield and less pollution. (3) Halogen ions in ionic liquids can be analyzed by Ultraviolet Spectrophotometric Determination because ionic liquid solution containing [Cl-I2]- or [Br-I2]- has a strong characteristic absorption in UV region. This method is available with high accuracy and sensitivity for both hydrophobic and hydrophilic ionic liquids.4. Three nitrate ionic liquids are prepared for catalytic oxidation of benzyl alcohol with molecular oxygen. Benzyl alcohol is converted to benzaldehyde with high effecincy and clean oxidation using proton ionic liquids (pyridinium nitrate) both as solvent and catalyst. The influence of the amounts of ionic liquids and reaction temperature are discussed. After optimization, the yield of the reaction is up to 95%. This catalyst system is simple and cheap without other organic solvents. Proton ionic liquid catalyst can be easily separated from the reaction system for the recycle of catalytic system.5. Four novel ionic liquids based on 1-methyl-3-octylimidazolium cation have been obtained with dichromate, molybdate, tungstate, and antimonate anions, respectively: 1-methyl-3-octylimidazolium dichromate, 1-methyl-3-octylimidazolium molybdate, 1-methyl-3-octylimidazolium tungstate, 1-methyl-3-octylimidazolium antimonate. Their melting point, density, conductivity, viscosity, electrochemical window, thermal stability and solubility have been investigated. Three nano metallic oxides have been synthesized using ionic liquid as the solvent, template and resource of metal. The nano materials are characterized by XRD,TEM and show small size and various shapes. It exhibits the application potential of ionic liquids in the preparation of special nano-materials.
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