Silicon phthalocyanine derivative

Table 3 Photophysical and photobiological properties of silicon(IV) phthalocyanine derivatives with...

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. 

PTD has been evaluated in the treatment of transfused blood going into blood banks, the objective being to inactivate viruses, such as HIV, without affecting erythrocytes. Use of silicon phthalocyanine or naphthalocyanine derivatives allows irradiation at wavelengths where the erythrocytes do not absorb, and the process is reported to be very effective. The use of Photofrin in inactivating HIV-1 in blood has also been described, whilst BPD (see Figure 4.23) has been used to inactivate feline leukaemia retrovirus in both spiked human blood and infected cat s blood. ... 

A series of axially-disubstituted silicon-phthalocyanines 353 (silicon-Pcs, Figure 23) was obtained by the nucleophilic displacement of one or two chlorine leaving groups from either PhSi(Pc)Cl or Si(Pc)Cl2, respectively, by reaction with the acid or alkoxide derivative of the ligand. Structure of these compounds was confirmed by H and 13C NMR, UV-vis absorption and emission spectra, electrospray or MALDI-ToF mass spectrometry as well as X-ray crystallography <2006T9433>. 

Thus (XX) reacts with phenol in pyridine to form diphenoxysilicon phthalocyanine (XXII), with benzyl alcohol to form (XXIII), and with triphenylsilanol to form (XXIV) (168,170, 200). These complexes sublime readily without decomposition (cf. corresponding aluminum derivatives). Bis(diphenylmethylsiloxy)silicon phthalocyanine, which melts before subliming, is one of the very few metal phthalocyanines which actually melt (873). The siloxy complex (XXIV) may also be prepared in benzyl alcohol, thus implying that the Si—O—Si(Pc)—0—Si backbone is more stable than C—O—Si(Pc)—O—C. The dibenzyloxy derivative (XXIII) reacts with diphenylsilanediol to form bis(benzyloxydiphenylsiloxy)silicon phthalocyanine (XXV). 

Cook, M.J., R. Hersans, J. McMurdo, and D.A. Russell (1996). Self-assembled monolayers of phthalocyanine derivatives on glass and silicon. J. Mater. Chem. 6, 149. 

Note Photosensitizers are as follows Photofrin , polyhematoporphyrin ethers ALA, aminolevulinic acid mTHPc, meta-tetetrahydroxyphenylchlo-rin SnET2, tin etiopurpurin, Lutetium Texaphyrin, a pendadentate aromatic metalloporphyrin BPD-MA, benzoporphyrin derivative mono acid HPPH, 2-[l-hexyloxyethyl]-devinylpyropheophorbide-a PC4, a silicon phthalocyanine AMD, age-related macular degeneration. 

Three publications deal with the synthesis of p-oxo-linked silicon phthalocyanine and porphyrin derivatives. The stepwise syntheses of p-oxo-linked hetero-chromophore arrays containing phthalocyanine, porphyrin, and sub phthalocyanine silicon and germanium complexes have been described [306, 307]. The p-oxo... 

The silicon(IV) phthalocyanine (12) is also effective in the photoinactivation of the parasite Plasmodium falciparum384 and various enveloped viruses in red blood cell concentrates.385-387 Other silicon (and aluminum) phthalocyanines have been evaluated for the photoinactivation of viruses cationic derivatives appear to be most effective.388... 

A recent review covers the redox chemistry of monomeric and oligomeric phthalocyanines in the form of monomers and stacks174. Of the group 14 elements, the electrochemical redox data described concerns mostly silicon derivatives and one germanium compound, m -oxobis(tetra-t -butyl) phthalocyanatogermanium175. 

A dye molecule that has found widespread attention in the synthetic metals community is phthalocyanine 186, which can be readily made from ortho-dicyanobenzene 187 in a metal-assisted cyclotetramerization that directly provides metal complex derivatives 188 (see scheme 44) [251]. A tuning of the electronic properties is possible via the central atom and, for example, by proceeding to the related tetranaphthalene compound 189 [252]. The importance of phthalocyanines 188 in both fundamental and industrial research comes from the great number of possible applications [253]. Also, 188 can be stacked into columnar arrays by using axial ligands at the metals or by linking silicon centers as central atoms by suitable spacers [254]. The introduction of long chain alkoxy... 

In addition to the alkoxymethyl derivatives, dihydroxosilicon(IV) phthalocyanines bearing alkoxy peripheral groups were prepared ((1) M = Si(OH)2, R = OC H2 +i, n = 2, 4, 6, 8, 10, 12, 14, 16, 18), and all displayed a Colh phase at low temperatures, with a decreasing mesophase stability due to the presence of axial hydroxyl groups.Similar silicon and silicon-free phthalocyanines substituted by chiral (S)-citronellol were shown to form a Colh and, at higher temperatures, a Col, with a helicoidal structure. 

With the development of organic semicondnctors which support electron or hole transport (in analogy of p- and n-type inorganic semiconductors) bilayer type p-n heterojunction devices have been constructed. In the case when organic p- and n-type materials are deposited consecutively in two layers we get lateral heterojunction devices which mimic classical p-n junction junction solar cells based on silicon. The first such cell was designed by Tang and pnb-lished in 1986 (Fignre 3)." Copper phthalocyanine was utilized as electron donor (p-type) material, whereas pery-lene derivative was nsed as electron acceptor connterpart (n-type material). 

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