| Due to the damage of traditional chemical industry for the earth’s environment, in the premise of sustainable development as the goal, the scientists put forward the concept of "green chemistry", which can be from the production source to prevent and control environmental pollution."Green chemistry" as one of the methods, skills, knowledge and talent of chemists can be used to avoid the threat to human health and the environment in all types of chemical processes, therefore,"green chemistry" has become environmental friendly chemistry, and achieve the efficient use of energy and resources and circulation by the environmental friendly way.Compared with the traditional method of organic chemistry, organic electrosynthesis using the "electrons", this clean reaction reagent, not only avoid the use of other toxic reagents, but also have the advantage of simple steps and higher product purity, better selectivity, and more conducive to industrialization.Carbon dioxide is one of gases leading to the green house effect. In the atmosphere, carbon dioxide content is continuously increasing with the expansion of industrial processes and energy-related activities, which has caused serious environmental problems. Thus, the conversion and utilization of CO2have attracted extensively attention in the whole world.There are two parts about the experiments in the paper. The details are given as follows:The first part:under room temperature and atmospheric pressure, in the two rooms type electrolytic cell, acetonitrile as solvent in which containing some supporting electrolyte, under the condition of constant current electrolysis activated acetonitrile, then add2-methylbut-3-yn-2-ol and cuprous halide to the cathode chamber, stirring in CO2, to synthesis a-alkenyl cyclic carbonate. Besides, examined respectively the influence of supporting electrolyte, amount of catalyst, charge, current density, electrode materials etc to electrosynthesis a-alkenyl cyclic carbonate on yield and obtained the optimized experimental conditions as follows:under normal temperature and atmosphere of N2, in the two rooms type electrolytic cell,0.1mol/L TBABr-MeCN in the cathode chamber,0.2mol/L TEAI-MeCN in the anode chamber, Cu as the cathode, Pt as anode, with current density of22.2mA/cm2electrolysis to charge of1F/mol, and stop the electrolysis. Then, add2-methylbut-3-yn-2-ol and cuprous chloride (the usage of the reactants2-methylbut-3-yn-2-ol is molar weight of0.35times) to the cathode chamber, stirring in CO2atmosphere, the product will be the most high yield rate was59.4%.At the same time, under the optimized conditions, when subetrate are other propargyl alcohols compound, also can electrosynthesis a-alkenyl cyclic carbonate, and presume to its possible mechanism.The second part:on the basis of first part experiments, concluded that yield is different when the types of propargyl alcohol substrates are different. Especially when the substrate is fragrant tertiary propargyl alcohols, ketones start generate. In this section, our work mainly aimed at the study of this phenomenon:2,2-diphenylprop-2-yn-l-ol as the standard material, analysis and discussion experimental results the above. At the same time, optimized the experimental conditions such as the concentration of substrates, supporting electolyte, charge, current density and the electrode material. The optimized reaction conditions as follows:under normal temperature and atmosphere of N2, two rooms type electrolytic cell,0.1mol/L TEAI-MeCN in the cathode chamber,0.2mol/L TEAI-MeCN in the anode chamber, Cu electrodes are cathode, Pt anode, with constant current density of17.3mA/cm2electrolysis to charge of0.5F/mol, can get the target product most high yield rate was63.6%, and speculate on the possible reaction mechanism. |
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