Search results for "anion effect"
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Insights into the anion effect on the self assembly of perylene bisimide diimidazolium salts
2017
Abstract We studied how changing the anion affects the self-assembly of three diimidazolium salts bearing a perylene bisimide spacer. In particular we used [BF 4 − ] and [NTf 2 − ] based salts together with a mixed salt bearing both [I − ] and [BF 4 − ] anions. Thermal as well as concentration and temperature dependent spectroscopic investigations revealed that changing the anion impacts on solid state and solution aggregation, leading to articulate thermotropic behaviors and contrasting solvent effects, respectively. We also studied the electrochemical behavior of the salts to verify if changing the anion alters the redox properties of the salts. Finally, different anions also lead to very…
STABILITY AND ORGANOCATALYTIC EFFICIENCY OF N-HETEROCYCLIC CARBENES ELECTROGENERATED IN ORGANIC SOLVENTS FROM IMIDAZOLIUM IONIC LIQUIDS
2015
The kinetic of degradation of 1-butyl-3-methylimidazole-2-ylidene (selected as model N-heterocyclic carbene - NHC), generated in organic solvents by cathodic reduction of the parent 1-butyl-3- methylimidazolium salts BMIm-X, was studied by a simple voltammetric analysis. The effect of NHC degradation rate on the efficiency of an organocatalyzed reaction (the synthesis of g-butyrolactone from cinnamaldehyde and trifluoromethylacetophenone) was investigated. The nature of the solvent and of the anion X have a remarkable effect on the stability of the NHC, the bis(trifluoromethylsulfonyl) imide anion being the best for a long lasting carbene (while acetonitrile seems to be the worst solvent). …