Subject phthalocyanines

Dioxazine Violet. Carba2ole Dioxa2ine Violet is prepared by the reaction of two moles of 2-ainino-A/-ethylcarba2ole with chloranil. This violet may be used in most plastics for shading phthalocyanine blues, because it has comparable light fastness. At relatively high temperatures, it may be subject to slow decomposition. 

A second reaction which is very often used for the preparation of phthalonitriles, although the yields are usually not reproducible, is the Rosenmund-von Braun reaction (see Houben-Weyl, Vol. E5, p 1460).106 107 Herein, a benzene derivative with a 1,2-dibromidc or 1,2-dich-loride unit is treated with copper(I) cyanide in dimethylformamidc or pyridine. During this reaction the formation of the respective copper phthalocyanine often occurs. This can be used as an easy procedure for the exclusive synthesis of copper phthalocyanines (see Section 2.1.1.7.),1 os-109 but can also lead to problems if the phthalonitrile is required as the product. For example, if l,2-dibromo-4-trifluoromethyl-benzene is subjected to a Rosenmund-von Braun reaction no 4-trifluoromethylphthalonitrile but only copper tetra(tri-fluoromethyljphthalocyanine is isolated.110... 

A detailed comparison [181] of three vinylsulphone dyes included a low-substantivity monoazo N-acetyl H acid derivative (Cl Reactive Red 35), a monoazo N-acetyl J acid type of higher substantivity (Cl Reactive Orange 82) and a phthalocyanine turquoise somewhat prone to aggregation (Cl Reactive Blue 21). Dyeings of these individual products were subjected to three wash-off procedures ... 

A series of zinc(II) phthalocyanines with other sorts of solubilizing groups in exo or endo positions (carboxyalkyl, carboxyalkoxy, amino acid) has been synthesized and subjected to preliminary in vitro assays.257 Interestingly, the seryl derivative zinc(II) 2,9,16,23-tetrakis(l-car-boxy-2-hydroxyethylaminocarbonyl)phthalocyanine proved to be cytotoxic (i.e., toxic in the dark) which is not so commonly observed with macrocyclic systems. 

In activated sludge, 80.6% degraded after a 47-h time period (Pal et al., 1980). Chemical/Physical. Zhang and Rusling (1993) evaluated the bicontinuous microemulsion of surfactant/oil/water as a medium for the dechlorination of polychlorinated biphenyls by electrochemical catalytic reduction. The microemulsion (20 mL) contained didodecyldi-methylammonium bromide, dodecane, and water at 21, 57, and 22 wt %, respectively. The catalyst used was zinc phthalocyanine (2.5 nM). When PCB-1221 (72 mg), the emulsion and catalyst were subjected to a current of mA/cm on 11.2 cm lead electrode for 10 h, a dechlorination yield of 99% was achieved. Reaction products included a monochlorobiphenyl (0.9 mg), biphenyl, and reduced alkylbenzene derivatives. 

Other donors very often used in combination with fullerenes comprise ferrocene, phthalocyanine, transition metal complexes, aniline derivatives, tetrathiafulvalene and oligoacenes, carotenoids, oligoarylene, and oligothiophene and many examples are collected in recent reviews and books dedicated to this subject.3a,7e 28... 

The V02+ phthalocyanine [VO(pc)] has been the subject of patents as it is useful in photoelectrophoretic and xerographic imaging.887 It can exist in at least three solid phases888 and the structure of so-called phase II was determined.889 It is composed of sheets of parallel and overlapping [VO(pc)] molecules and no discrete dimer pair exists. The vanadium is five-coordinate and square pyramidal, and is 0.575 A above the plane of the four nitrogens. The V—N distances do not differ significantly with a mean of 2.026 A the V=0 distance is 1 1.580 A. 

An electrocatalytic reaction is an electrode reaction sensitive to the properties of the electrode surface. An electrocatalyst participates in promoting or suppressing an electrode reaction or reaction path without itself being transformed. For example, oxygen reduction electrode kinetics are enhanced by some five orders of magnitude from iron to platinum in alkaline solutions or from bare carbon to carbon electrodes modified with Fe phthalocyanines or phenylporphyrins. For a comprehensive discussion of the subject, the reader is referred to refs. (76, 95, and 132-136). 

The subject matter of this chapter will be subdivided into sections concerning template synthesis of the complexes structural and thermodynamic properties of the complexes with synthetic cyclic polyamines complexes with mixed-donor macrocycles reactivity of the complexes cryptates and complexes with phthalocyanines and porphyrins. 

Molecular self-assembly will not be considered here (see [9.2]) in fact, it is a special type of synthetic procedure where several reactions between several reagents occur in one experimental operation to yield the final covalent structure it is subject to control by the intramolecular conformational features of intermediates and by the stereochemistry of the reaction(s) the efficient assembly of a covalent structure may require that the connecting reaction(s) be reversible so as to allow searching for the final structure. Examples are found in the generation of macropolycyclic structures by multiple (amine-aldehyde) condensations (see Section 4.1) or of porphyrinogens, porphyrins and phthalocyanins (see also in [9.13a]. 

The present article reviews the photochemical deactivation modes and properties of electronically excited metallotetrapyrroles. Of the wide variety of complexes possessing a tetrapyrrole ligand and their highly structured systems, the subject of this survey is mainly synthetic complexes of porphyrins, chlorins, corrins, phthalocyanines, and naphthalocyanines. All known types of photochemical reactions of excited metallotetrapyrroles are classified. As criteria for the classification, both the nature of the primary photochemical step and the net overall chemical change, are taken. Each of the classes is exemplified by several recent results, and discussed. The data on exciplex and excimer formation processes involving excited metallotetrapyrroles are included. Various branches of practical utilization of the photochemical and photophysical properties of tetrapyrrole complexes are shown. Motives for further development and perspectives in photochemistry of metallotetrapyrroles are evaluated. 

The present article will focus in particular on structurally characterized complexes and will refer to current trends and potential applications, simultaneously aiming at a coherent picture of the entire family of organometallic lanthanide amides including the inorganic derivatives. The elements Sc, Y, La will be treated as lanthanide elements Ln. Previous reviews cover this subject mostly as an aspect wrapped up under a comprehensive depiction of both metal amides [19] and lanthanide chemistry [20]. Other articles focus on special topics in this field, e.g., inorganic amides [21], silylamides [22], phthalocyanines [23] or porphyrins [24],... 

The last category was concerned with miscellaneous subjects, while citing some chirogenic porphyrin-based systems. Representative reviews include chiral lanthanide complexes by Aspinall [41], coordination chemistry of tin porphyrins by Arnold and Blok [42], photoprocesses of copper complexes that bind to DNA by McMillin and McNett [43], nonplanar porphyrins and their significance in proteins by Shelnutt et al. [44], cytochrome P450 biomimetic systems by Feiters, Rowan, and Nolte [45] and phthalocyanines by Kobayashi [46,47]. 

In such a large subject, this article can only focus on certain aspects, namely those that involve complexation with inorganic substrates. We only consider the synthetic macrocycles, with emphasis on transition metal complexation. Aza, oxa, and, to a lesser extent, thia and phospha macrocycles are also covered. The naturally occurring porphyrins, corrins, corphins, chlorins, and phthalocyanins, as well as the cyclodextrins, are not included. Because of the general complexity of macrocychc systems and the resulting complicated systematic names, commonly used abbreviations or simplified names will be employed. This review will encompass the synthesis, thermodynamics, stmcture, and applications of macrocychc ligands. 

Iron(ll) Phthalocyanine (FePc). The phthalocyanines and porphyrins are closely related, and share the first- and second-nearest neighbors of the centrally-located metal atom. While the S=1 nature of their ground state is unambiguous, the exact term symbol has been the subject of a large series of studies with often conflicting... 

We have shown that perfluorination of the phthalocyanine ligand enhances the stability and catalytic activity of RuFiePc. Encapsulation of this complex in zeolite NaX by the synthesis method dramatically improves the activity and selectivity of RuFiePc. These results suggest that RuFi Pc-NaX is one of the best alkane oxidation catalysts of its kind. Although cycloalkanes are readily oxidized, the complete range of possible substrates is uncertain at this point. The oxidation of other alkanes and olefins will be the subject of continuing studies. 

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