Phthalo cyanines

Structurally, the molecule is formed by the union of one atom of the metal with four molecules of phthalonitrile. Copper phthalo-cyanine is typical, and has the formula... 

A. Schmidt, L. K. Chau, A. Back, and N. R. Armstrong, Epitaxial Phthalocyanine Ultrathin Films Grown by Organic Molecular Beam Epitaxy (OMBE), in Phthalo-cyanines, Vol. 4, C. Leznof and A. P. B. Lever, eds., VCH Publications, 1996. 

In the presence of metal compounds the products are 2,9,16,23-tetrasubstituted metal phthalo-cyanines, e.g. 3. 

Metal atoms with a stable oxidation state of + IV are known to form unsubstituted bis(phthalo-cyanines) 9,10. They can be prepared by the reaction of a metal phthalocyanine, or an appropriate metal salt, and an alkali-metal phthalocyanine. 

Similarly, when copper(II) hexadecachlorophthalocyanine is treated with ethanol and potassium hydroxide at 145 °C for two hours and then at 160-1803C for a further two hours, a mixture of a variety of structural isomers of octachloro- and octaethoxy-substituted phthalo-cyanines is formed in 35 % yield.340... 

Naphthalocyanine (nc) species (Scheme 3) are structurally similar to the simpler phthalo-cyanines described above and have two isomers, denoted here (2,3-nc) and (1,2-nc). 

Although direct reaction of lanthanide mono-porphyrins with free phthalo-cyanine or its lithium derivatives is generally more efficient than the template synthesis, and gives rise to mixed-ligand complexes, the template strategy can also be applied for synthesis of phthalocyanine-porphyrin complexes, as in the case of unsymmetric bisphthalocyanine complexes (Scheme 8.2, B(b)) [106, 136, 145, 146]. Thus, metallation of free porphyrins with lanthanide salts in TCB or n-octanol leads to single-decker complexes, which then react with phthalonitriles under the action of DBU in alcoholic media to give the desired compounds. 

Fig. 11 Correlation between electrochemical potentials and OMTS bands for more than ten compounds including polyacenes, phthalo-cyanines, and porphyrins. OMTS data were acquired both from tunnel junctions and STM measurements. The standard potential relative to the normal hydrogen electrode associated with the half reaction M(solution) + e-(vac) —> M-(solution) is the y axis. The three outliers are assigned to the ring oxidation of porphyrins. (Reprinted with permission from [26])...

All polycyclic pigments, with the exception of triphenylmethyl derivatives, comprise anellated aromatic and/or heteroaromatic moieties. In commercial pigments, these may range from systems such as diketopyrrolo-pyrrol derivatives, which feature two five-membered heteroaromatic fused rings (DPP pigments) to such eight-membered ring systems as flavanthrone or pyranthrone. The phthalo-cyanine skeleton with its polycylic metal complex is somewhat unique in this respect. 

Another approach is based on n-n stacking, which utilizes the moderately strong interactions between delocalized n-electrons of nanocarbons and those in aromatic organic compounds, such as derivatives of pyrene [54,55], porphyrins [56,57], phthalo-cyanines [58] or combinations thereof [59], as well as peptides [60], DNA [61], benzyl alcohol [62] or triphenylphosphine [63]. These molecules are often modified with long... 

Kulprathipanja, S., Vora, B.V., and Li, Y. (1999) Method for treating a liquid stream contaminated with an iodide-containing compound using a solid absorbent comprising a metal phthalo-cyanine. U.S. Patent 6,007,724. 

Table 4.4 Electrophotographic data of solution coated near-IR absorbing phthalo-cyanines (Pc)...

Penmans P, Eorrest SR (2001) Very-high-efficiency double-heterostructure copper phthalo-cyanine/Cgo photovoltaic cells. Appl Phys Lett 79 126... 

Historically, most of the PS tested for their antimicrobial properties were already knovm to be effective for cancer treatment. They include the following classes of organic dyes porphyrin-related structures, phthalo-cyanines, phenothiazinium dyes, xanthylium dyes, and cationic fuller-enes (Dai et ah, 2009) (Table 3.3). 

For instance, the value of AE = 1.7 eV measured for single crystals of phthalo-cyanine, leads us to conclude that the 18-ji-electron system is responsible for both light absorption and conduction. 

It should be stressed here that the conductivities of e.g. polymers with phthalo-cyanine-type structure vary between 6.3 x 10 3 and 2.1 x 10 10 1 1 with activation energies down to 0.04 eV 8,68,69) The best conducting dye polymers showed a maximum of . 

Electrocatalysis takes place during the first step of 02 reduction, H202 being formed in a two-electron step. The correctness of this assumption is supported by polarographic investigations of 02 reduction in the presence of phthalo-cyanines 49h... 

Manecke et al.16s synthesized a semiconducting polymeric complex which possessed both bis(ethylene-l,2-dithiolato)Cu(II) and a phthalocyanine-Cu(II)-type structure 54. This Cu complex exhibited high catalytic activity in the oxidative polymerization of XOH, about 50 times higher than that of pyridine-Cu. A synchronous four-electron-transfer mechanism was proposed for the catalysis of 54. The phthalo-cyanine-Cu(II) type structure of 54 is presumed to form a complex with molecular... 

The photosensitivity spectra of the saturated polymers containing phthalo-cyanine are shown in Fig. 49 [286]. The photosensitivity is due to the presence of the dye. The pure p form magnesium phthalocyanine has nearly the same spectra. Apparently the polymer matrix environment promotes the P-form formation. The long wavelength maximum is related to the aggregated dye form with solvent inclusion. 

One such reaction that has been studied is the electrocatalytic reduction of oxygen directly to water.25,27 The electrocatalysts for this process are often based on metal porphyrins and phthalo-cyanins. Thus a graphite electrode whose surface was modified by the irreversible adsorption of a cofacial dicobalt porphyrin dimer was able to reduce oxygen under conditions where the reduction did not occur on the bare electrode itself. Similarly, a catalytic chemically modified electrode for the oxidation of chloride to chlorine has been prepared28 where the active catalyst was reported to be a ruthenium dimer, [(bipy)2(OH)RulvORuvO(bipy)2]4+, which was reduced to the corresponding [Rum-RuIV] dimer during the reaction. 

Heilmeier, G. H., and S. E. Harrison Charge transfer in copper phthalo-cyanine single crystals. Phys. Rev. 132, 2010 (1963). 

Figure 4. Change in conductivity with time of various phthalo-cyanine-coated electrodes exposed to exponentially diluted vapors. Initial concentration was 100 ppm for ammonia and DMMP but 1000 ppm for water and ethanol. The central atom of the phthalocyanine ring is indicated near each curve.

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