Soluble phthalocyanines

Besides the technical method starting from naphthalene, phthalic acid and its substituted derivatives can be prepared by oxidation of o-xylene to phthalic acid with potassium permanganate. This compound can be subsequently transformed via an anhydride, imide, and amide to a derivative of phthalonitrile, which is the more convenient starting material for several coordination compounds. The synthesis of the ferf-butyl-substituted dicarbonitrile, which is a very common starting material for highly soluble phthalocyanines, is shown below.97,105... 

Soluble phthalocyanines 6 are often prepared in a solution or suspension of the reactants. 

Water-soluble phthalocyanine dyes may contain only sulfonic acid groups but normally contain both sulfonic acid and sulfonamido groups. They are used as direct dyes for paper and as reactive dyes for cotton. Representative examples are Cl Direct Blue 199 (38) and Cl Reactive Blue 71 (39). These dyes are also used for the ink jet printing of textiles (see Section 9.12.6.2). 

Baxter, A. G. W. Bostock, S. Greenwood, D. (ICI). Water-Soluble Phthalocyanine Black Dyes from Cellulose Reactive Groups and Suitable for Use in Inks. U.S. Patent 4,705,528, November 10,1987. 

It should be mentioned that the impact of excited metallotetrapyrroles on biological systems is not limited to the above areas. It was found and patented [280] that some water-soluble phthalocyanine complexes exhibit bactericidal action on wet cotton fabric exposed to air and solar radiation. Zn(TPPS) is one of the best sensitizers in photokilling the unarmoured dinoflagellate Ptychodis-cus brevis. In the future further directions of photobiological applications of metallotetrapyrroles may emerge. 

Recently, a ruthenium-catalysed oxidation in water was published by d Alessandro et al. [34]. Water can be regarded as an environmentally friendly solvent which, because it is inert, reduces the risk of explosions. The oxidation of cyclohexane directly to adipic acid was performed using ruthenium catalysts bearing water-soluble phthalocyanine ligands RuPcS (where PcS is tetra-sodium 2,3-tetrasulfophthalocyaninato) with KHSOs (Eq. 4). However we note that very low TONs were observed and the use of KHSOs as a primary oxidant is not viable for industrial-scale oxidations. 

Mantareva V, Kussovski V, Angelov I, et al. Photodynamic activity of water-soluble phthalocyanine zinc(II) complexes against pathogenic microorganisms. Bioorgan Med Chem 2007 15 4829-35. 

Purification of the products is best effected by sublimation at 400°C in vacuo. However, not all phthalocyanines will sublime recrystallization from chlorobenzene, quinoline, or chloronaphthalene may then be employed. Certain more soluble phthalocyanines may be Soxhlet-extracted with lower boiling solvents such as acetone or alcohol. 

Ambipolar behavior has also been observed in BBL and poly(thiophene-3-propionic acid, anunoninm salt).[297] 51a showed n-channel mobihties of 0.04-0.06 cm V s and 0.02-0.03 cm V s for p-channel operation. 51c showed valnes of 0.5-0.7 cm V s for n channel and 1.2-1.7 cm V s for p-channel with on/off ratios between 2 and 50 for devices operated in air. A similar mechanism involving ion-modulated electrochemical conduction, as described above for water soluble phthalocyanines was proposed by the authors. 

W.M. Sharman, S.V. Kudrevich, J.E. van Lier (1996). Novel water-soluble phthalocyanines substituted with phosphonate moieties on the benzo rings. Tetrahedron Lett., 37, 5831-5834. 

Fietzek C., Bodenhoefer K., Haisch P., Hees M., Hanack M., Steinbrecher S., Zhou R, Plies R., and Gdpel W., Soluble phthalocyanines as coatings for quartz-microbalances Specific and unspecific sorption of volatile organic compounds. Sens. Actuators B, 57, 88-98,1999. 

Ozturk Z. Z., Zhou R., Weimar U., Ahsen V., Bekarogju O., and Gdpel W., Soluble phthalocyanines for the detection of organic solvents Thin film structures with quartz microbalance and capacitance transducers. Sens. Actuators B, 26-27, 208-212, 1995. 

One of the main problems with many of the photosensitisers mentioned above is that their specificity for tumour cells over healthy cells is not great enough. Even in a promising new family of second-generation photosensitisers, such as the water-soluble phthalocyanines, the specificity for tumour cells over healthy cells is only about 4 1. This means that under illumination, healthy tissue will experience some photodamage. 

Schneider, G., Wohrle, D., Spiller, W., Stark,)., and Schulz-EklofF, G. (1998) Photooxidation of 2-mercaptoethanol by various water soluble phthalocyanines in aqueous alkaline solution under irradiation with visible light. Photochem. Photohiol, 60, 333-342. 

Dihydroxy-phthalocyaninato-silicium(IV) (200 mg) (Aldrich) was heated in vacuo ( 10 torr) for 12 h at 440 °C. The polymer was obtained in a yield of 190 mg (-100%). If better soluble phthalocyanines such as octaalkoxy-substituted derivatives are used, the reaction can be carried out in boiling toluene under catalysis of FeCU [211]. 

Zagal, J., P. Bindra, and E. Yeager (1980). A mechanistic study of O2 reduction on water soluble phthalocyanines adsorbed on graphite electrodes. J. Electrochem. Soc. 127, 1506-1517. 

Such soluble phthalocyanine compounds can be dissolved in polymer films and used as near infrared radiation absorbents of sunlight. Two interesting apphcation... 

Such soluble phthalocyanine compounds can be dissolved in polymer films, and used as a near infrared ray absorbent of sunlight. Two interesting appUcation fields have been proposed, as a shield of heat rays [7] and as a controller of plant growth in agriculture [8]. 

Unsymmetrically substituted water-soluble phthalocyanines and naphthalocyanines as well as water-soluble tetrasubstituted phthalocyanines [R4PCM, R = COOH, SO3H M = Zn, A1(0] have been applied in photodynamic cancer therapy [109]. 

Karaoglu HRP, Koca A, Kocak MB (2012) Synthesis, electrochemical and spectroelectrochemical charactmization of novel soluble phthalocyanines bearing chloro and quatmnizable bulky substituents on peripheral positions. Dyes Pigm 92(3) 1005-1017... 

Lokesh K, Shivaraj Y, Dayananda B, Chandra S (2009) Layer-by-layer self assembly of a water-soluble phthalocyanine on gold. Application to the electrochemical determination of hydrogen peroxide. Bioelectrochem 75 104-109... 

Copper phthalocyanine 67 is an important example of a group of blue to green organic pigments. Phthalocyanines may be made water soluble by sulfonation, and the soluble phthalocyanine sulfates are important as direct dyes in the dyestuffs industry. 

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