title: γ-Cyclodextrin cuprate sandwich-type complexes.
abstract: Three structures, based on γ-cyclodextrin (γ-CD) and metal ions (Cu(2+), Li(+), Na(+), and Rb(+)), have been prepared in aqueous and alkaline media and characterized structurally by single-crystal X-ray diffraction. Their dimeric assemblies adopt cylindrical channels along the c axes in the crystals. Coordinative and hydrogen bonding between the cylinders and the solvent molecules lead to the formation of two-dimensional sheets, with the identity of the alkali-metal ion strongly influencing the precise nature of the solid-state structures. In the case of the Rb(+) complex, coordinative bonding involving the Rb(+) ions leads to the formation of an extended two-dimensional structure. Nonbound solvent molecules can be removed, and gas isotherm analyses confirm the permanent porosity of these new complexes. Carbon dioxide (CO2) adsorption studies show that the extended structure, obtained upon crystallization of the Rb(+)-based sandwich-type dimers, has the highest CO2 sequestration ability of the three γ-CD complexes reported.
authors: Petrochemicals Research Institute, King Abdulaziz City for Science and Technology, P.O. Box 6086, Riyadh 11442, Saudi Arabia. abagabas@hotmail.com
authors: Abdulaziz A
authors: AA
authors: Bagabas
authors: Marco
authors: M
authors: Frasconi
authors: Julien
authors: J
authors: Iehl
authors: Brad
authors: B
authors: Hauser
authors: Omar K
authors: OK
authors: Farha
authors: Joseph T
authors: JT
authors: Hupp
authors: Karel J
authors: KJ
authors: Hartlieb
authors: Youssry Y
authors: YY
authors: Botros
authors: J Fraser
authors: JF
authors: Stoddart