Inclusion complex of ferrocene(Fc) with β-cyclodextrin(β-CD) has been synthesized in ethylene glycol. It was unsolvable in water and had been successfully used in the preparation of β-CD-Fc inclusion complex modifi...Inclusion complex of ferrocene(Fc) with β-cyclodextrin(β-CD) has been synthesized in ethylene glycol. It was unsolvable in water and had been successfully used in the preparation of β-CD-Fc inclusion complex modified carbon paste electrode (CFCPE). Using the inclusion complex as the electroactive substance greatly increased the stability and reproducibility of CFCPE than using Fc.展开更多
Two functionalized calixarenes in cone conformation L 2-3 have been synthesized and their intramolecular inclusion complexes (1∶1) with organic neutral molecules CH 3CN and CH 3NO 2 have been prepared and c...Two functionalized calixarenes in cone conformation L 2-3 have been synthesized and their intramolecular inclusion complexes (1∶1) with organic neutral molecules CH 3CN and CH 3NO 2 have been prepared and characterized, respectively. The X-ray crystallographic analysis shows that L 2 in L 2·CH 3CN·C 2H 5OH has C 4 symmestry and L 3 in L 3·CH 3NO 2 exhibits C 2 symmestry. The CH-π aromatic interactions between the CH group of the guest and the phenyl rings of the calix backbond have been proved to be able to stabilize the intramolecular inclusion complexes formed. The interaction is directional, but it is independent of the acidity of the guest. To gain information on CH-π interactions, suitable geometrical parameters have been calculated from the crystal data of intramolecular inclusion complexes. The results show that L 3·CH 3NO 2 with L 3 in C 2 symmestry can also be bound stably in the intramolecular inclusion complex, being consistent with the thermal analysis. The geometrical parameters and the results of the thermal analysis of L 1·CH 3CN and L 1·CH 3NO 2 were also given and discussed.展开更多
Host-guest supramolecular gels were developed via the self-assembly of inclusion complexes(ICs) ofβ-cyclodextrins/phenylboronic acid gelator(PBA).Salts and current were involved in the self-assembly to stabilize the ...Host-guest supramolecular gels were developed via the self-assembly of inclusion complexes(ICs) ofβ-cyclodextrins/phenylboronic acid gelator(PBA).Salts and current were involved in the self-assembly to stabilize the host-guest gels.The stability of the gels was greatly improved after salts were added.The stable time of gels was extended from 2.5 h to 120 h with the addition of NH_4 NO_3 at the concentration of 2.5×10^(-2) g/mL.The morphology of the gel was affected by the concentrations of NH_4NO_3.SEM images revealed that the gels were three-dimensional nanofibrous networks,the sizes of fibers decreased with decreasing NH_4NO_3 concentrations,which affected the stability of gels,further proved by the rheological properties of gels.More stable gels were obtained with current stimulation,the stable time of the gel was increased from 2.5 h to 55 h with current by adding NaBF_4.The current also exhibited significant influence on the aggregation as the voltage varied(0-500 mV) with a constant concentration of salts.The result showed the self-assembly process of host-guest gel could be well controlled via the addition of salts and current to desired morphology and stability.展开更多
An equation for determining the equilibrium association constant (KA) of cyclodextrin inclusion complex with fluorescence anisotropy is derived and used to determine KA of pyrene-B-cyclodextrin inclusion complex. The ...An equation for determining the equilibrium association constant (KA) of cyclodextrin inclusion complex with fluorescence anisotropy is derived and used to determine KA of pyrene-B-cyclodextrin inclusion complex. The existing forms of cyclodextrin inclusion complex in solution, the interaction type of host with guest, and the possibility of application of B-cyclodextrin in the analysis of metal ions using naphthalene derivative as a ligand are discussed based on the equation derived along with the curve of fluorescence anisotropy versus cyclodextrin concentration of guest/cyclodextrin system.展开更多
Quantum chemical calculations were carried out to investigate the structures and properties for the inclusion complexes of nitrobenzene （NB） into β-cyclodextrin. Two low-energy conformations of β-cyclodextrin （A ...Quantum chemical calculations were carried out to investigate the structures and properties for the inclusion complexes of nitrobenzene （NB） into β-cyclodextrin. Two low-energy conformations of β-cyclodextrin （A and B） in the gas phase were initially investigated by the PM3 and B3LYP/6-31＋G（d,p） calculations, respectively. Three different orientations were considered in the inclusion process of A and B with NB to form 1：1 complexes. Potential energy scan by PM3 calculations indicated that the phenyl orientation Ab for conformation A and the equator orientation Bc for conformation B are more favorable in energy, respectively. We also considered the 2：1 inclusion complexes of host A or B with guest NB in the gas phase. PM3 calculation indicated that the host-guest interaction energies to form 1：1 complexes are more negative than those to form 2：1 NB/B complexes. Finally, we studied the solvent effect of NB/CD complex, and PM3 results show that the influence of water molecules on the inclusion process is very important. The driving forces for the inclusion process and the geometries of complexes were discussed in detail.展开更多
Two inclusion complexes of β-cyclodextrin-7-hydroxycoumarin （1） and ,β-cyclodextrin-4-hydroxycoumarin （2） were prepared and their crystal structures were investigated by single crystal X-ray crystallography unde...Two inclusion complexes of β-cyclodextrin-7-hydroxycoumarin （1） and ,β-cyclodextrin-4-hydroxycoumarin （2） were prepared and their crystal structures were investigated by single crystal X-ray crystallography under cryogenic condition. Both structures consist of stacks of face-to-face cyclodextrin dimers arranged in brickwork-like pattern along the crystallographic a-axis. For complex 1, each of the two dimeric β-cyclodextrins includes one 7-hydroxycoumarin molecule that penetrates deeply into the cyclodextrin dimer and locates its lactonering at the center of the dimer cavity. For complex 2, each cyelodextrin dimer accommodates three 4-hydroxycoumarin molecules. One of them is sandwiched between two units of the cyclodextrin dimer, the other two are shallowly included in the cavities of the dimeric cyclodextrins respectively and protrude their lactone rings from the primary end of the cyclodextrin. The substituent effects of guest molecules on inclusion geometry of various coumarin molecules in fl-cyclodextrin were examined.展开更多
文摘Inclusion complex of ferrocene(Fc) with β-cyclodextrin(β-CD) has been synthesized in ethylene glycol. It was unsolvable in water and had been successfully used in the preparation of β-CD-Fc inclusion complex modified carbon paste electrode (CFCPE). Using the inclusion complex as the electroactive substance greatly increased the stability and reproducibility of CFCPE than using Fc.
基金theNationalNaturalScienceFoundationofChina (No .2 9872 0 34 )andtheNaturalScienceFoundationofHenan ,China
文摘Two functionalized calixarenes in cone conformation L 2-3 have been synthesized and their intramolecular inclusion complexes (1∶1) with organic neutral molecules CH 3CN and CH 3NO 2 have been prepared and characterized, respectively. The X-ray crystallographic analysis shows that L 2 in L 2·CH 3CN·C 2H 5OH has C 4 symmestry and L 3 in L 3·CH 3NO 2 exhibits C 2 symmestry. The CH-π aromatic interactions between the CH group of the guest and the phenyl rings of the calix backbond have been proved to be able to stabilize the intramolecular inclusion complexes formed. The interaction is directional, but it is independent of the acidity of the guest. To gain information on CH-π interactions, suitable geometrical parameters have been calculated from the crystal data of intramolecular inclusion complexes. The results show that L 3·CH 3NO 2 with L 3 in C 2 symmestry can also be bound stably in the intramolecular inclusion complex, being consistent with the thermal analysis. The geometrical parameters and the results of the thermal analysis of L 1·CH 3CN and L 1·CH 3NO 2 were also given and discussed.
基金financial support from the National Natural Science Foundation of China(No.21672164)Wenzhou Science and Technology Bureau(No.Y20170162)Graduate Innovation Fund of Wenzhou University(No.3162018031)。
文摘Host-guest supramolecular gels were developed via the self-assembly of inclusion complexes(ICs) ofβ-cyclodextrins/phenylboronic acid gelator(PBA).Salts and current were involved in the self-assembly to stabilize the host-guest gels.The stability of the gels was greatly improved after salts were added.The stable time of gels was extended from 2.5 h to 120 h with the addition of NH_4 NO_3 at the concentration of 2.5×10^(-2) g/mL.The morphology of the gel was affected by the concentrations of NH_4NO_3.SEM images revealed that the gels were three-dimensional nanofibrous networks,the sizes of fibers decreased with decreasing NH_4NO_3 concentrations,which affected the stability of gels,further proved by the rheological properties of gels.More stable gels were obtained with current stimulation,the stable time of the gel was increased from 2.5 h to 55 h with current by adding NaBF_4.The current also exhibited significant influence on the aggregation as the voltage varied(0-500 mV) with a constant concentration of salts.The result showed the self-assembly process of host-guest gel could be well controlled via the addition of salts and current to desired morphology and stability.
文摘An equation for determining the equilibrium association constant (KA) of cyclodextrin inclusion complex with fluorescence anisotropy is derived and used to determine KA of pyrene-B-cyclodextrin inclusion complex. The existing forms of cyclodextrin inclusion complex in solution, the interaction type of host with guest, and the possibility of application of B-cyclodextrin in the analysis of metal ions using naphthalene derivative as a ligand are discussed based on the equation derived along with the curve of fluorescence anisotropy versus cyclodextrin concentration of guest/cyclodextrin system.
基金Supported by the National Natural Science Foundation of China (No. 20773107, 20877049)China Postdoctoral Science Foundation (No. 20080431123)Jiangsu Planned Projects for Postdoctoral Research Funds (No. 0801020C)
文摘Quantum chemical calculations were carried out to investigate the structures and properties for the inclusion complexes of nitrobenzene （NB） into β-cyclodextrin. Two low-energy conformations of β-cyclodextrin （A and B） in the gas phase were initially investigated by the PM3 and B3LYP/6-31＋G（d,p） calculations, respectively. Three different orientations were considered in the inclusion process of A and B with NB to form 1：1 complexes. Potential energy scan by PM3 calculations indicated that the phenyl orientation Ab for conformation A and the equator orientation Bc for conformation B are more favorable in energy, respectively. We also considered the 2：1 inclusion complexes of host A or B with guest NB in the gas phase. PM3 calculation indicated that the host-guest interaction energies to form 1：1 complexes are more negative than those to form 2：1 NB/B complexes. Finally, we studied the solvent effect of NB/CD complex, and PM3 results show that the influence of water molecules on the inclusion process is very important. The driving forces for the inclusion process and the geometries of complexes were discussed in detail.
基金Project supported by the Natural Science Foundation of Hainan Province （No. 808145）.
文摘Two inclusion complexes of β-cyclodextrin-7-hydroxycoumarin （1） and ,β-cyclodextrin-4-hydroxycoumarin （2） were prepared and their crystal structures were investigated by single crystal X-ray crystallography under cryogenic condition. Both structures consist of stacks of face-to-face cyclodextrin dimers arranged in brickwork-like pattern along the crystallographic a-axis. For complex 1, each of the two dimeric β-cyclodextrins includes one 7-hydroxycoumarin molecule that penetrates deeply into the cyclodextrin dimer and locates its lactonering at the center of the dimer cavity. For complex 2, each cyelodextrin dimer accommodates three 4-hydroxycoumarin molecules. One of them is sandwiched between two units of the cyclodextrin dimer, the other two are shallowly included in the cavities of the dimeric cyclodextrins respectively and protrude their lactone rings from the primary end of the cyclodextrin. The substituent effects of guest molecules on inclusion geometry of various coumarin molecules in fl-cyclodextrin were examined.
