Coordination polymers phthalocyanines

Scheme 6 represents coordinate polymers. A low-molecular-weight compound with multidentate groups on both ends of the molecule grows into a linear polymer with metal ions, and the polymer chain is composed of coordinate bonds. The parquetlike polymer complexes, poly(metal-phthalocyanine) and poly(metal-tetracyano-ethylene), are classified into Scheme 7. They are formed by inserting metal ions into planar-network polymers or by causing a low-molecular-weight ligand derivative to react with a metal salt and a condensation reagent.

Zinc(II) phthalocyanine 55 bearing two pyridyl substituents is also capable of forming a self-assembled array [56], This compound forms intermolecular zinc-nitrogen coordinated species in solution and self-assembles to form a coordination polymer in the solid state. As shown in the crystal structure revealed by singlecrystal X-ray diffraction analysis, the compound self-assembles in an edge-to-face manner forming a zig-zag polymer in the solid state (Fig. 3). 

Recently, Shirai and Hojo25) have reported the synthesis of the soluble coordinate polymers containing metal-phthalocyanines in the main chain according to Scheme 2 (Eq. 7). The polymers obtained by polycondensation of metal-phthalocyanines bearing peripheral carboxy groups attached to various aromatics, -QH4-, -CsHr-CHz-CgH, exhibit higher conductivities (10-11 10-6 Q cm-1) than the corresponding monomer complexes. 

The synthesis and characterization of coordination polymers was supported by the U.S. Air Force in a search for materials that exhibited high thermal stabilities. However, attempts to prepare stable, tractable coordination polymers that simulate the exceptional thermal and/or chemical stability of model monomeric coordination compounds such as copper(II) ethylenediaminobisacetylacetonate or phthalocyanine have been disappointing ". Typically, only short chains are formed, and the thermally stable monomers lose most of their stability when linked by the metals into polymeric units. The principles in designing coordination polymers are ... 

Coordination Polymers Based on Phthalocyanine Ligands and Related Macrocycles... 

SiPcs axially substituted with 3- or 4-pyridyloxy moieties have been nsed as bnilding blocks in the formation of alternating coordination polymers when mixed with zinc(n) octathiobutoxy (R = nBu) or octathiophenoxy phthalocyanine (R = Ph) (Figure 9)P The fairly low binding constant, about 300-400 M , between the two Pc-based supramolecular monomers, SiPc and ZnPc, shows how weak the metal-ligand interaction between a pyridine... 

Figure 9 Coordination polymer formed by a zinc phthalo-cyanine and bis-3-pyridyloxy silicon phthalocyanine.

Figure 27 Bis-4-pyridyl zinc phthalocyanine 40, and its coordinating polymer in the solid state.

This chapter describes the synthesis and properties of a number of classes of polymers containing metal coordination complexes in their structures. These polymers are prepared by polymerization reactions of metal-containing monomers and through metal coordination reactions. Schiff base-containing polymers (5) were one of the earUest classes of coordination polymers examined. Polymers incorporating macro-cycUc porphyrins and phthalocyanines (7) in their backbones and sidechains are known to exhibit interesting optical and electrical properties. The best-studied classes of metal-containing polymers contain bipyridyl and other related units coordinated to metal ions (8). 

Changing the macrocycles in the coordination polymers shown in Fig. 1 from phthalocyanine to one with an extended x-electron system, e.g. 2,3-naphthalocyanine leads to an interesting effect concerning the semiconducting properties of the corresponding bridged systems. A systematic investigation of the oxidation potentials of the metallomacrocycles used for... 

Unique combinations of properties continue to be discovered in inorganic and organometallic macromolecules and serve to continue a high level of interest with regard to potential applications. Thus, Allcock describes his collaborative work with Shriver (p. 250) that led to ionically conducting polyphosphazene/salt complexes with the highest ambient temperature ionic conductivities known for polymer/salt electrolytes. Electronic conductivity is found via the partial oxidation of unusual phthalocyanine siloxanes (Marks, p. 224) which contain six-coordinate rather than the usual four-coordinate Si. 

The phthalocyanine moiety (LXa), where M represents a coordinated metal, has been incorporated into polymer structures. LXa is abbreviated by structure LXb. One reaction... 

Soluble, swellable and macroporous chelate polymers with coordinative and covalent bonds (Chaps. 2, 3) may be prqiared. Structure investigations are in most cases possible with conventional method. The advantage of coordinative tmding is the ease of preparation. But on the other side aich a bond is not so strong when compared with a covalent one. So the application must decide between coordinative or covalent bond. Reversible binding of small molecules, catalysis and photoredox reactions may be important. Cheaper, easier to prepare and more stable phthalocyanines, oximes and Schiffbase chelates will find higher practical interest then porphyrins. 

Evaporating Al(OH)Pc and Ga(OH)Pc with aqueous HF led after heating to fluoroaluminium and fluorogallium phthalocyanine polymers [Al(F)Pc] , [Ga(F)Pc] (79)125-128). The polymers were purified by sublimation. The bond between the Pc in the staple is described as combined covalent coordinative linkage. 

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