Structure and host-guest properties of the nanoporous diaquatetrakis(p-nitrobenzoato)dicopper(II) framework

摘要

Cu-2(p-O2NC6H4CO2)(4)(H2O)(2)]. Me2CO has been prepared and characterized by single crystal X-ray diffraction. The Cu-Cu distance is 2.608(1) Angstrom with the four p-nitrobenzoate ligands coordinated in bidentately bridging fashion, such that the copper atoms have a square pyramidal coordination. It possesses a framework structure with continuous channels parallel to the c axis with an opening size of approximate to5.6x7.9 Angstrom, giving a solvent accessible volume of 22% of the crystal volume. The framework remains intact and crystalline after removal of the included acetone molecule, as determined by X-ray powder diffraction. It is shown, by thermogravimetric measurements, that also benzene and water guest molecules can reversibly be incorporated and released. For comparison, [Cu-2(p-O2NC6H4CO2)(4)(EtOH)(2)] was prepared and characterized by single crystal X-ray diffraction. Here, the channels are occupied by the axial ethanol ligands. [References: 52