Porous coordination polymers channels

TMA can coordinate to not only Cu2+ to form the typical 3-D framework polymer but also to Co2+ to form a porous host-guest compound Co(TMA) (py) with a different structure. The guest pyridine molecules in this compound may be removed from the channels without the collapse of the framework, and the pyridine-removed porous material adsorbs other guest molecules.[187] Polymerization of TMA with a Ni2+ macro-cyclic complex leads to a porous coordination polymer with a unique structure. In the... 

Through coordination of O-bridged trinuclear Zn2+ clusters with chiral ligands, chiral porous coordination polymers may be obtained.[207] Because the two enantiomers of the ligand may be isolated separately, the obtained porous coordination polymers may also be present as the separate enantiomers. The guest water molecules in the polymer channels may be reversibly adsorbed and desorbed, and this lays the foundation for these... 

R. Kitaura, K. Seki, G. Akiyama, and S. Kitagawa, Porous Coordination-polymer Crystals with Gated Channels Specific for Supercritical Gases. Angew. Chem., Int. Ed., 2003, 42, 428-431. 

Early reports of metalloligands include Cu complexes that contain oxamate, oxamide, benzoate, or propionate.Utilization of the metalloligand, [ Cu(2,4-pydca)2(H20) 2Et3NH] (pydca = pyridine-2,4-dicarboxylate) as a linker provides a porous coordination polymer, [ ZnCu-(2,4-pydca)2(H20)3(DMF) DMF] , where Zn ion at the node of the network acts as a connector and the Cu ions in the channel walls are available for guest coordination, as illustrated in... 

Kitaura R, Seki K, AMyama G et al (2003) Porous coordination-polymer crystals with gated channels specific for supercritical gases. Angew Chem Int Ed 42 428 31... 

The level of sophistication of stable radicals may increase in the near future as it is becoming clear that the performance of catalysts can be improved by tuning both steric and electronic effects of these radicals. " Another successful approach is the use of heterogenized radicals. Thus, a free-radical porous coordination polymer [Cu(DPIO)2(SiF6)] [DPIO = 4,7-bis(4-pyridyl)-l,l,3,3-tetramethylisoindolin-2-yloxyl] (Fig. 7), possesses one-dimensional channels with incorporated nitroxyl catalytic sites. 

S. Subramanian, M. J. Zaworotko, "Porous solids by design IZn(4,4 -bpy)2(SiF6)]n-xDMU a single framework octahedral coordination polymer with large square channels , Angew. Chem, Int. Ed. Engl 1995,34,2127-2129. 

Bilayer architectures formed in M2(2)3(N03)4 n (where M = Co, Ni and Zn) were one of the first systems of coordination polymers to be shown as porous materials [43]. The bilayer architectures interdigitate with each other leaving small channels in the crystal lattice which were occupied by solvated water molecules. Powder X-ray studies indicate that the water molecules can be removed from the network without causing any distortion or decomposition of the network. The adsorption studies of water removed and dried sample indicated that the material is capable of adsorbing CH4, N2 and 02. About 2.3 mmol of CH4 and 0.80 mmol of N2 or 02 are adsorbed per gram of anhydrous material. The adsorption-readsorption followed the same isotherm, indicating the stability of the network throughout the process. Further, the isotherms for the adsorption-readsorption can be classified as type I in the IUPAC classification [48]. 

Chen and coworkers have reported that a series of multidimensional porous polymers with 3d f mixed metals could recognize some specific cations. For example, two 3d-4f het-erometallic coordination polymers ([Ln(L15)3Mni.5(H20)3]-3.25 HyOlco [L15=pyridine-2,6-dicarboxylic acid Ln = Eu (Eu-15) Ln = Tb (Tb-15)] with ID-channels could recognize Zn + to some extent [38]. The emission intensity of Eu-15 gradually increased upon addition of... 

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