| Nine novel ionic liquids, which have not been reported, were prepared, six of them are based on diacetoneacrylamide cation(DA) and anions of acetate(Ac), trifluoroacetate(TF), chlorinate(Cl), sulphate(SO), tetrafluoroborate(BF) and hexafluorophosphate(PF); two of them based on Schiff base cation and the anions of acetate, trifluoroacetate and another is ammonium diacetate.They are characterized by FT-IR, 1H NMR, 13C NMR, XRD, element analysis (EA) and water content analysis. The results show that the ionic liquids based on diacetoneacrylamide cation exist by hydrated salts, such as DAAc 2H2O, DATF 2H2O, DAC1H2O, DASOH2O, DABFH2O and DAPFH2O; the molecular formula of the two based on Schiff base cation are SB(CH3COO)2 and SB(CF3COO)2; and that of ammonium diacetate is NH4H(CH3COO)2.The melting points of them and their other physical properties, such as conductivity, viscosity, solubility and thermo stability were determined. Synchronously, their electrochemical potential windows were also determined by means of the cyclic valtommetry of these compounds at different temperatures.The prepared ionic liquids DABF, DASO, DAPF, DAC1, DATF and DAAc were used as catalysts in the esterification reaction of acetic acid with C1-C6 and octanol. The results display that the salts with stronger acidity, such as DABF, DASO, DAPF and DAC1 have higher catalytic activity, and the activity of DATF and DAAc for the esterification is weaker. The thermodynamics of ethyl acetate synthesis by the esterification of acetic acid and ethanol was explored in the presence of DABF as catalyst, showing that the reaction is an equilibrium one. In order to obtained more product of ester, the following measures must be carried out: (1) increasing the molar ratio of alcohol to acid; (2) the solvents such as benzene, cyclohexane etc must be added in the system so as to remove the produced water in the process of esterification.When using benzene as dehydration reagent and DABF as catalyst, the conversion of acetic acid is 99.7%, selectivity of ethyl acetate is 100% at the molarratio of alcohol/ acid 0.28/0.175; its atom economy percent is 82.77%, approaching to the inherent one of this reaction (83.02%). However, the catalyst can be recycled for 5 times and the remarkable reduction of the product yield was not observed. In addition, we investigated the esterification rules of acetic acid with methanol, ethanol, isopropanol, butanol, isobutanol, amyl alcohol, isoamyl alcohol, cyclohexanol and octanol, which are in accord with the report in the literature.Dimerization of a-methylstyrene (AMS) catalyzed by acidic ionic liquids, such as Et3NHCl-AlCl3 and Et3NHCl-FeCl3, and the effect of different organic solvents to the catalytic reaction were investigated. The results show that the ionic liquid Et3NHCl-AlCl3 is an effective catalyst for the dimerization. The reaction was carried out by itself exothermic heat in the absence of solvents. At the reaction temperature of 80C and within the reaction time of 5 min, conversion of AMS is 100%, the selectivity of saturated dimer 1,1, 3-trimethyl-3-phenylindan is high up to 97.3%. However, the reason that the main product is cyclic dimer 1, 1, 3-trimethyl-3-phenylindan and the reaction is accelerated was explained by the investigation of the dimerization mechanism. Alkylaminium-ferric chloride Et3NHCl-FeCl3 has also catalytic activity for the dimerization, although its activity is lower than that of Et3NHCl-AlCl3 because of its lower acidity. Moreover, the main product of the dimerization was converted into the linear dimer 4-methyl-2, 4-diphenyl-1-pentene in the presence of Et3NHCl-FeCl3 as catalyst when polar solvents, such as tertiary butanol and tertiary amyl alcohol etc., were added in. So the effect of different solvents, such as methanol, ethanol, butanol, tertiary butanol, isoamyl alcohol, tertiary amyl alcohol, diethyl ether and cyclohexane, on the reaction was explored. The results show that the selectivity of linear dimer 4-methyl-2, 4-diphenyl-l-pentene is 100% in the presence of tertiary but...
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