Phthalocyanines examples, with derivatives

Fig. 2 Examples of photosensitizers presently approved for clinical applications or in clinical studies. mTHPC, tetra (meso-hydroxy) phenyl chlorin BPD-MA, benzoporphyrin derivative Photofrin is a mixture of several compounds where dimers or trimers of the indicated structure are assumed to be of major importance PpIX, protoporphyrin IX - accumulating upon treatment with 5-aminolevulinic acid or its ester derivatives, NPe6, HPPH, Hexyl pyropheophorbide TPPS2a, disulfonated (adjacent) tetraphenylporphin AlPcS2a, disulfonated (adjacent) aluminum phthalocyanine. Areas with ionic side groups are indicated in shadow...

In SPE, a small amount of organic solvent or surfactant is added to collected samples to prevent adsorption to sample containers. To increase recoveries of ng 1 levels of PAHs in SPE, ACN (40%) or surfactants above their CMC can be added to samples prior to preconcentration. Solid supports, chemically modified with copper phthalocyanine trisulfonic acid derivatives for selective sorption of PAHs, have been investigated. The selective interaction is thought to be with the tt electrons of the PAHs. Brij-35, a neutral polyoxyethylene lauryl ether surfactant was added above the CMC to water samples to prevent sorption on container walls. Before preconcentration by SPE, samples were diluted to reduce the surfactant concentration to just below the CMC. Recoveries of over 90% for SPE on solids containing copper phthalocyanine trisulfonic derivatives were obtained for spiked water samples at low ngl levels, except for NAP, ACE, and FLU. Experiments repeated using a C18 SPE preconcentration sorbent gave >90% recovery for all 16 EPA PAHs, except for ACY. Examples of the use of SDB as an SPE sorbent include the online analysis of seawater from the coast of Catalonia in Spain, where no PAHs above the low ng 1 level were detected, and the analysis of leachate from coal deposits. ... 

SELECTED EXAMPLES OF PHTHALOCYANINES AND THEIR DERIVATIVES WITH SPECIFIC PROPERTIES AND POSSIBLE APPLICATIONS... 

A number of phthalocyanine derivatives can be made by replacing the hydrogen atoms on the benzene rings. Pigment Green 7, mentioned above, is an example. Vat Blue 29 is a partially sulfonated cobalt phthalocyanine. Reduction with sodium hydrosulfite in caustic soda solution converts it to a soluble form that can be applied to textiles and reoxidized... 

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... 

Aluminum phthalocyanine (PcAlX) can be prepared from the phthalonitrile and aluminum trichloride either in refluxing quinoline138 13g or without a solvent under addition of ammonium molybdate(VI).137 The chloro compound can be transformed to a hydroxy derivative by treatment with sulfuric acid.58-140 Also, the insertion of aluminum in a metal-free phthalocyanine is possible, for example trialkylaluminum can be used.141,142... 

BNCT sensitisers are designed with neutron capture in mind, but those that are porphyrin/ phthalocyanine-based may show PDT activity. An example is the disodium (or dipotassium) salt of the tetrakis-carborane ester (58) derived from 3,8-bis(l,2-dihydroxyethyl)deuteroporphyrin.298 This is water soluble and tumor selective, showing high tumor/normal brain ratios.299 Photophysical properties are similar to other water-soluble porphyrins in rat glioma cells, specific localization in mitochondria is observed.300... 

In several cases—such as, for example, phthalocyanine and protoporphyrin IX derivatives— the energy red shift and broadening of the transition with pressure may be sufficient to ensure a thermal population of the excited state, by occupation of a ti orbital. As discussed above, the thermal occupation of excited states may lead in principle to the formation of a reaction product. 

An important area of research in silicon phthalocyanine chemistry has been the preparation of conducting polymers through Si—O—Si links.In one recent example, silicon phthalocyanine complexes have been appended to a den-drimer framework through Si—O—C(triazine) bonds formed by reaction of the salt Na [Si(Pc)(Ph)0 ] with a dichlorotriazine derivative. 

We can now make sensible guesses as to the order of rate constant for water replacement from coordination complexes of the metals tabulated. (With the formation of fused rings these relationships may no longer apply. Consider, for example, the slow reactions of metal ions with porphyrine derivatives (20) or with tetrasulfonated phthalocyanine, where the rate determining step in the incorporation of metal ion is the dissociation of the pyrrole N-H bond (164).) The reason for many earlier (mostly qualitative) observations on the behavior of complex ions can now be understood. The relative reaction rates of cations with the anion of thenoyltrifluoroacetone (113) and metal-aqua water exchange data from NMR studies (69) are much as expected. The rapid exchange of CN " with Hg(CN)4 2 or Zn(CN)4-2 or the very slow Hg(CN)+, Hg+2 isotopic exchange can be understood, when the dissociative rate constants are estimated. Reactions of the type M+a + L b = ML+(a "b) can be justifiably assumed rapid in the proposed mechanisms for the redox reactions of iron(III) with iodide (47) or thiosulfate (93) ions or when copper(II) reacts with cyanide ions (9). Finally relations between kinetic and thermodynamic parameters are shown by a variety of complex ions since the dissociation rate constant dominates the thermodynamic stability constant of the complex (127). A recently observed linear relation between the rate constant for dissociation of nickel complexes with a variety of pyridine bases and the acidity constant of the base arises from the constancy of the formation rate constant for these complexes (87). 

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... 

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