Phthalocyanines complexes and

The X-ray structure of zinc naphthalocyanate has been determined with Zn—N bond lengths of 1.983(4) A.829 Pentanuclear complexes with a zinc phthalocyanine core and four ruthenium subunits linked via a terpyridyl ligand demonstrate interaction between the photoactive and the redox active components of the molecule. The absorbance and fluorescence spectra showed considerable variation with the ruthenium subunits in place.830 Tetra-t-butylphthalocyaninato zinc coordinated by nitroxide radicals form excited-state phthalocyanine complexes and have been studied by time-resolved electron paramagnetic resonance.831... 

In a more quantitative study the redox properties of the phthalocyanine complex and the structurally similar tetraphenylporphyrins were studied by electrochemical methods in solution M). It was found that the oxidation/reduction may go by two distinctly different mechanisms ... 

Recently, Swager has compared the mesomorphic properties of an octakis(tetra-decyloxymethyl)-phthalocyanine coppeifll) complex, Crys 80-Colhd 280-I, with the analogous octakis(tetradecyloxymethyl)tetra-2,3-thiophenoporphyiazine, Crys 49-Colhd 258-I [134]. X-ray difiiaction studies show that the lattice constants are 33.5 A for the phthalocyanine complex and 32.9 A for the thiophenoporphyr-... 

Solid-Supported Surface Catalysis by Metal Complexes. Hong et al. (1987a, b, in press) have prepared a variety of hybrid catalysts between Co(II) phthalocyanine complexes and the surfaces of silica gel, polystyrene-divinylben-zene, and Ti02 and tested these hybrids for catalytic activity with respect to the autoxidation of hydrogen sulfide, sulfur dioxide, 2-mercaptoethanol, cysteine, and hydrazine ... 

Besides the substances mentioned so far, functionalized fuUerenes like the simple Bingel adduct can be intercalated into nanotubes as well (Section 2.5.5.2). The formation of peapods has further been described for metallocenes (e.g., ferrocene), porphyrines (e.g., erbium phthalocyanine complex) and small fragments of nanotubes. The most important prerequisite for the feasibility of inclusion is always a suitable proportion of sizes of both the tube and the structure to be embedded. For example, this effect can be observed for the intercalation of different cobaltocene derivatives into SWNT. The endohedral functionalization only takes place at an internal diameter of 0.92nm or above (Figure 3.100). But there is also an upper limit to successful incorporation. When the diameter of the nanotube is too large, the embedded species can easily diffuse away again from the host. Only few molecules are consequently found inside such a wide tube. 

The isoindole ring is present in the phthalocyanine complexes and one method for their preparation is from 1,3-diminodihydroisoindole which is prepared by cyclization of o-phthalonitrile (Scheme 25) <83JA1539>. 

Molecules that exhibit donor functions include chlorophyll, phthalocyanine complexes, and perylene. Examples for molecules with acceptor functionality are fiillerenes and MEH-PPV. 

Erdogmus A, Booysen I, Nyokong T (2011) Synthesis and electrochemical properties of new tetra substituted cobalt phthalocyanine complexes, and their application in electrode modification for the electrocatalysis of 1-cysteine. Synth Met 161 241-250... 

Ozoemena K, Nyokong T (2003) Electrochemical behaviour of thiol-derivatised zinc (II) phthalocyanine complexes and their self-immobilised films at gold electrodes. 

In order to make these oxidative reactions of 1,3-dienes catalytic, several reoxidants are used. In general, a stoichiometric amount of benzoquinone is used. Furthermore, Fe-phthalocyanine complex or Co-salen complex is used to reoxidize hydroquinone to benzoquinone. Also, it was found that the reaction is faster and stereoselectivity is higher when (phenylsulflnyl)benzoquinone (383) is used owing to coordination of the sulfinyl group to Pd, Thus the reaction can be carried out using catalytic amounts of PdfOAcji and (arylsulfinyl)benzoquinone in the presence of the Fe or Co complex under an oxygen atmosphere[320]. Oxidative dicyanation of butadiene takes place to give l,4-dicyano-2-butene(384) (40%) and l,2-dicyano-3-butene (385)[32l]. 

Halide complexes are also well known but complexes with nitrogen-containing ligands are rare. An exception is the blue phthalocyanine complex formed by reaction of Be metal with phthalonitrile, 1,2-C6H4(CN)2, and this affords an unusual example of planar 4-coordinate Be (Fig. 5.5). The complex readily picks up two molecules of H2O to form an extremely stable dihydrate, perhaps by dislodging 2 adjacent Be-N bonds and forming 2 Be-O bonds at the preferred tetrahedral angle above and below the plane of the macrocycle. 

Dirubidium phthalocyanine (PcRb2) and dicesium phthalocyanine (PcCs2) can be prepared by chemical-vapor deposition of benzene-1,2,4,5-tctracarbonitrile and the metal chloride.135 In the solid phase, additional rubidium atoms are complexed between peripheral cyano groups. 

Bis(phthalocyanines) are also accessible by the reaction of isoindolinediimine and suitable metal compounds. For example, zirconium(IV) chloride when treated with isoindolinediimine in refluxing quinoline under a nitrogen atmosphere for 2 hours gives a zirconium(IV) bis(phthalocyanine) complex. 

Many Co11 porphyrins (87)110 131 and phthalocyanine complexes (102)110 have been examined for their ability to function as catalytic chain transfer agents and much mechanistic work has focused on the use of these catalysts. The more widespread application of these complexes has been limited because they often have only sparing solubility and they are highly colored. 

Other reactions of small inorganic molecules are the oxidation of chloride ion at a Nafion electrode impregnated with a ruthenium 0x0 complex and the reduction of nitrogen monoxide to ammonia at a Co phthalocyanine modified electrode... 

Organometallic complexes are known which contain a wide variety of macrocycles closely related to porphyrins corroles, porphycenes, tetraazaporphyrins. phthalocyanines, tetraazaannulenes, and porphyrinogens are the best known examples. Examples containing the first four of these macrocycles are included where there is a useful comparison or contrast with the relevant porphyrin chemistry, but the discussion will not be comprehensive. The four macrocycles are shown in Fig. 2. 

Several examples of carbene complexes have been structurally characterized (Fig. 5), and selected data for Ru(TPP)(=C(C02Et)2)(Me0H). Os(TTP)-(=C(p-C(,H4Me)2)(THF), Os(TTP)(=CHSiMe2)(THF), Os(TTP)(=SiEt2THF)-(THF) and a /x-carbido phthalocyanine complex, Ru(Pc)(py)]2C, are given in Table The ruthenium carbene complex has a Ru=C bond signifi-... 

Previous studies by Sorokin with iron phthalocyanine catalysts made use of oxone in the oxidation of 2,3,6-trimethylphenol [134]. Here, 4 equiv. KHSO5 were necessary to achieve full conversion. Otherwise, a hexamethyl-biphenol is observed as minor side-product. Covalently supported iron phthalocyanine complexes also showed activity in the oxidation of phenols bearing functional groups (alcohols, double bonds, benzylic, and allylic positions) [135]. Besides, silica-supported iron phthalocyanine catalysts were reported in the synthesis of menadione [136]. 

We have demonstrated a new class of effective, recoverable thermormorphic CCT catalysts capable of producing colorless methacrylate oligomers with narrow polydispersity and low molecular weight. For controlled radical polymerization of simple alkyl methacrylates, the use of multiple polyethylene tails of moderate molecular weight (700 Da) gave the best balance of color control and catalyst activity. Porphyrin-derived thermomorphic catalysts met the criteria of easy separation from product resin and low catalyst loss per batch, but were too expensive for commercial implementation. However, the polyethylene-supported cobalt phthalocyanine complex is more economically viable due to its greater ease of synthesis. 

Since iron phthalocyanine complexes can be activated and stabilized by a chlorine ring substitution (12), the activity of iron hexadecachlorophthalocyanine (7b) immobilized on silica was examined for the synthesis of 4, 5, and 6 with TBHP as oxidant. 

Coordination of NO to the divalent tetrasulfonated phthalocyanine complex [Co(TSPc)]4 results in a complex formally represented as [(NO )Coin(TSPc)]4 kf= 142M-1s-1, KA 3.0 x 105 M-1). When adsorbed to a glassy carbon electrode, [Co(TSPc)]4- catalyzes the oxidation and reduction of NO with catalytic currents detectable even at nanomolar concentrations. Electrochemistry of the same complex in surfactant films has also been studied.905 Bent nitrosyl complexes of the paramagnetic trivalent tropocoronand complex Co(NO)(TC) ((189), R = NO) have also been reported.849... 

The redox potentials of zinc-substituted phthalocyanines are shown to be linearly dependent on the total Hammett substituent constant.837 In 1987, Stillman and co-workers used the absorption and magnetic circular dichroism spectra of the zinc phthalocyanine and its 7r-cation-radical species to assign the observed bands on the basis of theoretical calculations. The neutral and oxidized zinc phthalocyanine complexes with cyanide, imidazole, and pyridine were used with the key factor in these studies the stability of the 7r-cation-radical species.838 The structure of zinc chloro(phthalocyaninato) has been determined and conductivity investigated.839... 

A porphyrin compound with a 2,9-dimethyl- 1,10-phenanthroline functionality fused at the beta-pyrrole positions is a phthalocyanine analog, and formed a complex with zinc in the cavity and a further zinc binding to the phenanthroline group. The absorption and emission spectra of the compound with and without the external zinc demonstrated the strong effects of the second metal binding on the porphyrin 7r-system.840... 

The major types of complexes under intense investigation are the tetraden-tate Schiff base, for example, CoSalen, and phthalocyanine, for example, iron phthalocyanine complexes (Fig. 7.1).69... 

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