Spacers coordination polymers

Belcher, W. J., Longstaff, C. A., Neckenig, M. R., Steed, J. W., Channel-containing ID coordination polymers based on a linear dimetallic spacer. Chem. Commun. 2002, 1602-1603. 

Several metal-organic polymers assembled by dithioether ligands, which are functionalized by heteroelements such as O, N, or Si in the spacer unit, have been recently described and reacted with Cu(I) salts. For example, the 2D square-grid coordination polymer 37 incorporating the 16-membered dithiaoxa crown-ether L37 has been prepared by a self-assembly process involving the interaction of the dithiaoxa macrocycle with CuCN (Scheme 17) the parallel reaction of the dithiaoxa crown-ether with Cul afforded the ID double-stranded coordination polymer 37 . This example demonstrates, how the nature of the counterion can control the form of the network.157... 

Kim s group also prepared the l,12-diphenyl-5,8-dioxa-2,ll-dithidodecane ligand L44 and reacted it with Cul.164 Contrary to our failure to assemble a network with 1,8 bis(phenylthio)octane, L44 containing eight spacer units between the sulfur atoms allowed the construction of a 2D square-grid-type coordination polymer 44. This finding may be rationalized by the enhanced basicity of -S-benzyl vs. -S-phenyl (Scheme 23). 

In 2003, we first used self-assembled zinc(II) terpyridine polymers in the fabrication of PLEDs.22 We synthesized a series of monomers containing two terpyridine as chelating units, which are at opposite ends and separated by a spacer group (R) (Fig. 5). The self-assembled zinc(II) coordination polymers were easily prepared by the addition of Zn(OAc)2 into solution of monomers. The product yields were up to 80%, and the inherent viscosities of the polymers were in the range of 0.48 to 1.21 dL/g, as determined using an Ubbelohde viscometer in NMP at 30 0.1 °C. 

Probably the first examples of 3D self-catenated frameworks within coordination polymers were described by Robson and coworkers [49], In the species [Cd(CN)2L] [L = pyrazine or l,4-bis(4-pyridyl)butadiene] the Cd(CN)2 sublattices form 44 undulated layers that are joined in a criss-cross fashion by the L spacers. Catenated hexagonal chair-like circuits are observed in the interlayer connections (see Fig. 

Supramolecular and coordination polymer complexes supported by a tripodal tripyridine ligand containing a 1,3,5-triethylbenzene spacer, H. Ohi, Y. Tachi and S. Itoh, Inorg. Chem., 2004, 43, 4561. 

One of the most successful families is represented by a series of polymers built from the linkage of metallic carboxylate chains through 4,4 -bipyridine spacers [ 176]. As an example, the coordination polymer [Cu(C4H O )(4,4 -bpyifH O) ] is formed by the connection of chains of Cu(II) metal ions bridged by succinate ligands through 4,4 -bipyridine molecules. This 3-D framework shows weak ferromagnetic interactions and channels, in which the water molecules are located. 

A 1 1 mixture of AgBp4 and the linear spacer ligand 4,4 -bipyridine (4,4 -bipy, Fig. 4a) gives the one-dimensional coordination polymer [Ag(4,4 -bipy)]BF4 n containing linear two-coordinate silver(I) centers.Square-grid coordination polymers represent a common class of two-dimensional network. These structures are based upon a 1 2 ratio of metal centers containing square-planar coordination sites and linear spacer ligands such as 4,4 -... 

The second compound (Pan et al., 2003) has been obtained via hydrothermal methods by reacting a lanthanide ion with 1,4-phertylendiacetate (see scheme 3). The chemical formula of the obtained coordination polymer is Ln2(pda)3(H20) 2H2O with Ln = La or Er and (pda) = 1,4-phenylendiacetate. Its extended stmcture consists of Ln-COO triple helixes cross-linked through -CH2C6H4Q12- spacers of the (pda) anions, showing ID open chan-... 

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