A supramolecular inclusion complex between β-cyclodextrin(β-CD) and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two...A supramolecular inclusion complex between β-cyclodextrin(β-CD) and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two β-CD molecules, one α-naphthylacetic acid, two ethanols and twenty-eight water molecules in the asymmetric unit, which could be formulated as [(C42H70O35)2·(C12H10O2)·(C2H5OH)2·28H2O]. Two β-CD molecules constitute a dimer by face-to-face contact of their secondary hydroxyl sides. At the interface of the dimer, one α-naphthylacetic acid molecule is sandwiched between two β-CD molecules. Each β-CD unit of the dimer includes one ethanol molecule in its cavity. The β-CD dimers are linked together via hydrogen bonding to form layers that are stacked in a brickwork-like pattern. The comparative study of some sandwich complexes elucidates that the interface of the β-CD dimer has a stronger inclusion capacity than the cavity of β-CD for some suitable planar guest molecules. The novel inclusion structure results from the competitive inclusion of α-naphthylacetic acid and ethanol.展开更多
The inclusion complex of β-cyclodextrin (β-CD) with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains...The inclusion complex of β-cyclodextrin (β-CD) with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains two β-CDs, two 4-chlorobenzoic acids and twenty-nine water molecules in the asymmetric unit, and can be formulated as 2(C42H70O35)·2(CTH5O2Cl)·29(H2O). In the crystal lattice, two β-CDs form a face-to-face dimer jointed together through hydrogen bonding between the secondary hydroxyl groups of β--CDs. Two 4-chlorobenzoic acid molecules which contact by C-Cl…π interactions are included in the β-CD dimer cavity. The β-CD dimers are arranged in brickwork-like pattern along the crystallographic a-axis. The effect of guest molecule length on the inclusion geometry was discussed by comparative study of some fl-CD complexes containing similar guests.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
基金Supported by the Natural Science Foundation of Hainan Province, China(No.808145)the Doctoral Foundation of Hainan Normal University, China(No.103303)the Key Discipline of Hainan Province Organic Chemistry, China(No.006).
文摘A supramolecular inclusion complex between β-cyclodextrin(β-CD) and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two β-CD molecules, one α-naphthylacetic acid, two ethanols and twenty-eight water molecules in the asymmetric unit, which could be formulated as [(C42H70O35)2·(C12H10O2)·(C2H5OH)2·28H2O]. Two β-CD molecules constitute a dimer by face-to-face contact of their secondary hydroxyl sides. At the interface of the dimer, one α-naphthylacetic acid molecule is sandwiched between two β-CD molecules. Each β-CD unit of the dimer includes one ethanol molecule in its cavity. The β-CD dimers are linked together via hydrogen bonding to form layers that are stacked in a brickwork-like pattern. The comparative study of some sandwich complexes elucidates that the interface of the β-CD dimer has a stronger inclusion capacity than the cavity of β-CD for some suitable planar guest molecules. The novel inclusion structure results from the competitive inclusion of α-naphthylacetic acid and ethanol.
基金the financial support from the Natural Science Foundation of Hainan Province(no.808145)Doctoral Foundation of Hainan Normal University(no.103303)
文摘The inclusion complex of β-cyclodextrin (β-CD) with 4-chlorobenzoic acid was synthesized and its crystal structure was determined by single crystal X-ray diffraction under cryogenic condition. The complex contains two β-CDs, two 4-chlorobenzoic acids and twenty-nine water molecules in the asymmetric unit, and can be formulated as 2(C42H70O35)·2(CTH5O2Cl)·29(H2O). In the crystal lattice, two β-CDs form a face-to-face dimer jointed together through hydrogen bonding between the secondary hydroxyl groups of β--CDs. Two 4-chlorobenzoic acid molecules which contact by C-Cl…π interactions are included in the β-CD dimer cavity. The β-CD dimers are arranged in brickwork-like pattern along the crystallographic a-axis. The effect of guest molecule length on the inclusion geometry was discussed by comparative study of some fl-CD complexes containing similar guests.
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.