Phthalocyanines chelate complexes

Fig.1. Structures of porphyrin 1, chlorophyll 2, and phthalocyanine 3. In the presence of metal salts M"+X (M=metal, X=counter anion, n=oxidation state or number of counter anions), porphyrins produce chelate complexes. Some metal chelates of the porphyrins, such as ZnPor, form further coordination bonds with other ligands such as pyridines...

Phthalimide, JV-thio-metal complexes, 800 Phthalocyanines, 863-870 chelate complexes, 374 demetallation, 863 IR spectra, 861 mass spectra, 861 metallation, 863 NMR, 861 photochemistry, 869 reactions, 863 at metal, 869 redox chemistry, 870 spectra, 860 synthesis, 861 two-metal complexes, 868 Phytic acid zinc complexes, 985 2-Picoline... 

Very stable Co1 chelate complexes are obtained from phthalocyanine ligands (for example, 44 and 71). 

The crystallization of zeolites and molecular sieves with metal complexes represents a fresh strategy for the synthesis of these materials as well as a novel method for encapsulation of metal chelate complexes. We have shown that several first row tranistion metal phthalocyanines complexes can be encapsulated in X and A type zeolites by synthesizing the zeolite around the metal complex. Preliminary results indicate the concentration and type of phthalocyanine complex modify the crystallization of X type zeolites. The extension of this method to other metal chelate complexes and molecular sieves is currently under investigation. 

Savy et al. 35> reach practically the same conclusion concerning the electron transitions during formation of the activated complex but consider an edge-on arrangement of the oxygen above the plane of the chelate molecule more probable. Their studies relate only to the catalytic properties of the phthalocyanines for 02 reduction. Their conclusion is that the conditions for optimal activation of oxygen... 

We are still further from being able to explain the anodic activity of the CoTAA complex. The cobalt phthalocyanine, which is structurally identical with CoTAA in the inner coordination sphere, is completely inactive in the catalysis of anodic reactions. It therefore looks as if the central region is not exclusively responsible for the anodic activity. On the other hand, the fact that CoTAA is inactive for the oxidation of H2 points to n orbitals of the fuel participating in the formation of the chelate-fuel complex. A redox mechanism (cf. Section 5.2) can be ruled out because anodic oxidation proceeds only in the region below the redox potential of CoTAA (i.e. at about 600—650 mV). 

Direct Dyes. These water-soluble anionic dyes, when dyed from aqueous solution in the presence of electrolytes, are substantive to, i.e., have high affinity for, cellu-losic fibers. Their principal use is the dyeing of cotton and regenerated cellulose, paper, leather, and, to a lesser extent, nylon. Most of the dyes in this class are polyazo compounds, along with some stilbenes, phthalocyanines, and oxazines. Aftertreatments, frequently applied to the dyed material to improve washfastness properties, include chelation with salts of metals (usually copper or chromium), and treatment with formaldehyde or a cationic dye-complexing resin. 

As far as dyes are concerned, chelates of type Cb are termed 1 2 or symmetrical 1 2 metal complexes if the two tridentate ligands are equal, and mixed or unsymmetrical 1 2 metal complexes in the other case. Chelates of type Bb represent 1 1 metal complexes. The types Cb and Bb include, in general, azo and azo-methine metal complex dyes, whereas chelates of the quadridentate types Ac and Be are derived predominantly from formazan and phthalocyanine chromophores. 

In addition to the ligands above, considerable attention is given to more complex ligand systems [4,5] aromatic and heteroaromatic compounds (heteroarenes) (i.e., five- or six-member cyclic structures with delocalized 7i-bonds in the ring containing, besides carbon atoms, either N, P, As, O, S, Se, or Te compounds [6-8]), various chelate-forming compounds, such as macrocyclic crown-ethers, cryptands, porphyrins, and phthalocyanines. 

A large class of coordination compounds, metal chelates, is represented in relation to microwave treatment by a relatively small number of reported data, mainly p-diketonates. Thus, volatile copper) II) acetylacetonate was used for the preparation of copper thin films in Ar — H2 atmosphere at ambient temperature by microwave plasma-enhanced chemical vapor deposition (CVD) [735a]. The formed pure copper films with a resistance of 2 3 pS2 cm were deposited on Si substrates. It is noted that oxygen atoms were never detected in the deposited material since Cu — O intramolecular bonds are totally broken by microwave plasma-assisted decomposition of the copper complex. Another acetylacetonate, Zr(acac)4, was prepared from its hydrate Zr(acac)4 10H2O by microwave dehydration of the latter [726]. It is shown [704] that microwave treatment is an effective dehydration technique for various compounds and materials. Use of microwave irradiation in the synthesis of some transition metal phthalocyanines is reported in Sec. 5.1.1. Their relatives - porphyrins - were also obtained in this way [735b]. 

In addition to the complexation in solutions, pyridine-appended fulleropyrro-lidines can also form coordination complexes with zinc(II) phthalocyanines in solid-state thin films. Troshin et al. have investigated the photovoltaic behavior of bilayer solar cells fabricated by deposition of solution-processed fulleropy-rrolidines 36-40, which contain chelating pyridyl groups, on vacuum-evaporated films of unsubstituted zinc(II) phthalocyanine (ZnPc) [46], The UV-Vis spectra of these films resemble the spectrum of ZnPc recorded in pyridine, showing a sharp... 

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