Potassium complexes phthalocyanines

Bismuth phthalocyanines of the type PcBiX can be prepared in solution by the reaction of bismuth(III) halides with PcLi2 or in a molten mixture of phthalonitrile and bismuth(III) halide.166 The sandwich-like complex [Pc2Bi]- can be obtained by slowly adding potassium methoxide to a melt of bismuth(III) oxonitrate and phthalonitrile.167... 

In contrast to the ionic complexes of sodium, potassium, calcium, magnesium, barium, and cadmium, the ease with which transition metal complexes are formed (high constant of complex formation) can partly be attributed to the suitably sized atomic radii of the corresponding metals. Incorporated into the space provided by the comparatively rigid phthalocyanine ring, these metals fit best. An unfavorable volume ratio between the space within the phthalocyanine ring and the inserted metal, as is the case with the manganese complex, results in a low complex stability. 

TiOz coated with potassium ferrocyanide proved to be an effective catalyst for the reduction of C02 to formic acid and formaldehyde.169 A very stable and reproducible catalytic system was prepared by immobilizing Ni2+ and Ru2+ complexes into Nation membrane, which was used for the selective reduction of C02 to formic acid.170 Formic acid was again formed when Zn and Co phthalocyanines were adsorbed onto a Nation membrane on irradiation with visible light in acidic aqueous solution containing triethanolamine as a hole scavenger. Cobalt comns (B i2) acting as homogeneous catalysts in acetonitrile-methanol solutions induced the formation of formic acid and CO.172... 

Potassium peroxomonosulfate (Oxone ) is also an effective oxidizing agent for the epoxidation of various alkenes in the presence of Mn porphyrin and a PT catalyst [79]. The biphasic epoxidation of various olefins is readily catalyzed by Co and Ni" phthalocyanines with NaClO as the oxygen donor and Bu4N" Br" as the PT agent [80]. The PTC oxidation of alkenes with NaClO is also catalyzed by square-planar Ni complexes [81-83]. 

This is prepared from potassium amyloxide and phthalonitrile (10). Very little work appears to have been done with the complex. Heavier group IA metal phthalocyanines have not been reported. 

The zerovalent dipotassium phthalocyanine cuprate(0) may be prepared by the reduction of the cupric complex with potassium in liquid ammonia. It was not possible to isolate a copper(I) derivative (870). Like other low oxidation state metal phthalocyanines, this complex is air- and water-sensitive. 

Because of the limited solubility of metal phthalocyanines, the spectra are limited to the solid state. Most authors have used Nujol or halocarbon mulls, but Sidorov and Kotlyar (328) sublimed the complexes onto potassium chloride or bromide disks. The disks and samples were maintained at a temperature of about 100°C, as a result of which thin layers of the a modification were always produced. The /3 polymorphs were obtained by taking the disks and subjecting them to a temperature of 280°-300°C in vacuo for several hours, whereupon the a—>j3 transformation took place. The infrared spectra were then remeasured. The spectral characteristics of the a and 6 forms are almost independent of the central metal ion. In-... 

Electron microscopy of and a study of electron dilBfraction by a thin film of the complex formed between copper phthalocyanine and potassium have revealed a unique crystalline structure/ The electron micrographs showed that an island film structure existed, with single crystals of the complex being up to 1 /utm in diameter. The films were stable in vacuo, but on exposure to air they degraded over a period of 24 hours, after which only traces of the ordered structure were observable by electron diffraction. 

This instrument was employed to examine the excited state dynamics of supramolecular systems generated from self-assemblies between metal-substituted 18-crown-6 tetra-substituted phthalocyanines (McrPc) with ions contained in the crown sites (McrPcK) and metal-substituted weso-tetrakis(4-sulfonatophenyl)porphyrin (MTPPS) or meso-(4-carboxylphenyl)porphyrin (MTPPC). In the absence of added potassium ions, no hetero-complexes were formed. In the presence of K", absorption spectral changes indicated the formation of a... 

Lithium alkoxides play an important role in the oligomeric cyclization of dinitriles in the synthesis of phthalocyanines. The combination of potassium alkoxide-crown ether complex in a hydrocarbon solvent gives a very powerful catalyst for production of vinyl ethers from alcohols and acetylene (Eq. 7.9). ... 

Metallo-N4 complexes are easily adsorbed on different organic and inorganic matrices, which promoted the use of phthalocyanines or porphyrins adsorbed on, e.g., humic acids as heterogeneous catalysts in the chemical oxidation of phenols by potassium peroxymonosulfate, KHSO5 [34]. Fe(III)-TPPS, Mn(III)-TPyP, Fe(III)-TSPc and Cu(II)-TSPc were adsorbed on these matrices, the complexes with Mn (III) and Fe(ni) being the more efficient ones for phenols degradation. The higher efficiency in the presence of humic acids was attributed to the hydrophobic character of the latter, which contributed to the interaction of the catalyst with the phenols. 

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