Cadmium coordination polymers

Figure 2.4.4 View of a porous cadmium coordination polymer, Cd(N03)2[2,4 -(l,4-phenylene)bispyridine] °° [50], Such materials are a particular target for coordination polymer chemists and require rational, designed, synthetic approaches.

Two cadmium coordination polymers, [Cd(isonicotinate)2(H20)]-DMF and Cd3(isonicotinate)4(N03)2(4,4 -bipy)2(H20)2 have been synthesized and... 

A triazole-bridged cadmium coordination polymer, based on 3,5-dimethyl-4-amino-1,2,4-triazole, has been synthesized under hydrothermal conditions [17]. This material exhibits a strong blue fluorescence emission band in the solid state at ambient temperature. 

Li H, Wang H, Wang H, Li B. A novel (2,3,5)-connected double interpenetrating three-dimensional network cadmium coordination polymer with flexible tri(triazole) and dicyanamide ligands. Inorg Chem Commun 2011 14(1) 49-51. 

Li H, Liu G, Liu TT, Zhang HY, Yue F, Wang JD. Syntheses of triazole-bridged cadmium coordination polymer with luminescence properties. Russ J Coord Chem 2011 37(1) 8-11. 

Alkenes are well-established to be able to undergo [2+2] photodimerization reactions in the solid state if the double bonds are close enough together, and this can happen in coordination networks. Lang and coworkers showed that both silver and cadmium coordination polymers containing tra v-l,2-bis(4-pyridyl)ethylene (bpe) can undergo photodimerization, in the latter case in a SC-SC transformation. Vittal and coworkers showed that compounds such as [Zn(bpe)(bdc)] formed interpenetrated three-dimensional (3D) networks with the double bonds from the two networks <4 A apart. Following UV irradiation, the compounds were converted into the cyclobutane derivatives in SCSC transformations (equation 15). ... 

To date, only one example has been reported of a 2D cadmium coordination polymer constructed with thiocyanate and nicotinamide. In the referred polymer, each Cd " ion, located in a centrosymmetric octahedral environment, is coordinated by two nicotinamide molecules in traits positions and four thiocyanate ions, which act as N,S bridging ligands that link to four neighboring cadmium ions [70]. 

Synthesis of the Two-Dimensional Coordination Polymer 34 from Cadmium(II) and 4,4 -Bipyridine (Section 7.3.2.1) [109]... 

A) Mechanosynthesis of cadmium-cyanoguanidine coordination polymers, (B) Ex situ powder X-ray diffraction analysis of the 1 2 reaction between CdCIa and cnge carried out by preheating at 85°C for 1 h followed by 5-mln milling cycles. Notably, the 1 1 Cd(cnge)... 

Figure 9.6 Coordination polymer with cadmium nitrate [18],...

Ying J, Liu XJ, Tian AX, Wang XL. Assembly of a new cadmium(n)-bis(triazole) coordination polymer templated by keggin polyoxomet-alate. Z Anorg Allg Chem 2011 637(5) 613-7. 

Fujita, M., Y.J. Kwon, M. Miyazawa, and K. Ogura (1994). One-dimensional coordinate polymer involving heptacoordinate cadmium(ll) ions. J. Chem. Soc. Chem. Commun. 1977-1978. 

Qiu Y, Li Y, Peng G et al (2010) Cadmium metal-directed three-dimensional coordination polymers in situ tetrazole ligand synthesis, stractures, and luminescent propaties. Cryst Growth Des 10 1332-1340... 

An example of a nontrivial polyrotaxane formed using a similar synthetic approach is shown in Figure 21(b). In this case, rotaxane ligands bridge cadmium ions into 2D (4,4) sheets, and the wheels (in this case dibenzo-24-crown-8) can no longer be separated from the polymeric network. Indeed, while the previous example contained only rotaxane motifs, in this nontrivial example one can also define catenane-type interactions between the wheels and M4L4 rings formed by the coordination polymer. 

Chen LF, Li ZJ, Qin YY, Cheng J-K, Yao Y-G. Syntheses, crystal structures and photoluminescence of two new pyrazinecarboxylate-based cadmium(II) coordination polymers. J Mol Struct 2008 892 278-82. 

The structure determination of Zn(en)(NCS)Cl reveals monomeric tetrahedral zinc coordinated to thiocyanate via nitrogen.179 A structure determination of Cd(en)(N02)2 reveals a polymer containing cadmium in a seven-coordinate pentagonal prismatic environment the en functions as a bridging ligand, as does one of the nitrites.180... 

A number of zinc and cadmium complexes of adenine (82),554,555 adenine N-oxide,556 guanine,557 inosine,558 cytidine559 and other nucleosides560 have been studied. The structure of (9-methyladenine)ZnCl2 is polymeric each zinc ion is tetrahedrally coordinated to two chlorine atoms (Zn—Cl = 2.22 A), and to N-l and N-7 of neighbouring adenine moieties (Zn— N = 2.05A).561 A structural study of the related cadmium complex, CdCl2(DMSO)L (L = 9-methyladenine), has shown the complex to form a one-dimensional polymer. 2... 

The crystal structure of cadmium(II) formate dihydrate has been determined768 and consists of a three-dimensional polymer with each cadmium octahedrally coordinated. In a two-dimensional plane, the formates bridge in an anti,anti configuration, while in the perpendicular plane, the bridging is in a syn,anti manner. Water molecules occupy the remaining coordination... 

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