- UV-visible spectral study on the stability of lead phthalocyanine complexes
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UV-visible electronic spectral study has been done on lead phthalocyanine (PbPc), lead tetranitro phthalocyanine (PbTNP) and lead tetraamino phthalocyanine (PbTAP) in dimethyl sulphoxide (DMSO) and H2SO4 media. Metal free phthalocyanine (H2Pc) is insoluble in DMSO and soluble in conc. H2SO4. The study has been extended to H2Pc to compare the stability of phthalocyanine structure with the PbPc complexes in H2SO4 medium. PbPc complexes are stable in DMSO, and all the complexes are more stable in 36 N H2SO4 than in 30 N and 28 N H2SO4 media. Further, complete demetallation and degradation of the phthalocyanine structure have been observed for all the PbPc complexes in 36 N H2SO4 medium within a week's time. The stability of these complexes is compared with H2Pc in H2SO4 medium. The decomposition reactions in H2SO4 media for H2Pc, PbPc, PbTNP and PbTAP are followed spectrophotometrically and rate constants were calculated. The decomposition reactions were found to follow the first-order kinetics with respect to the concentration of their respective phthalocyanine derivatives.
- Mohan kumar,Achar
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- A series of phthalocyaninotin complexes
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Methods of preparing and purifying the compounds PcSnF2, PcSnBr2, PcSnI2, and PcSn(OH)2 are given together with improved procedures for the synthesis and purification of PcSnCl2, Pc2Sn, PcSn, and PcPb. Pc2Sn is shown to have two polymorphic modifications and to form a 1:1 solvate with 1-chloronaphthalene. Both polymorphs are found to undergo thermal decomposition at elevated temperatures with the formation of PcSn and PcH2.
- Kroenke, William J.,Kenney, Malcolm E.
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- Ohmic and space-charge-limited conduction in lead phthalocyanine thin films
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The electrical characteristics of thermally evaporated triclinic lead phthalocyanine thin films are studied. A number of parameters is evaluated on the basis of the theory of space-charge-limited conduction and the following values are obtained: permittivity ε = 3.16 × 10-11 F m-1; hole mobility μ ≈ 6.05 × 10-10 m2 V-1 s-1; room temperature hole concentration po ≈ 1.60 × 1018 m-3; concentration of traps per unit energy range at the valence band edge Po ≈ 2.79 × 1043 J-1 m-3; temperature parameter of trapping distribution Tt ≈ 770 K; total trap concentration Nt ≈ 2.97 × 1023 m-3. The room temperature electrical conductivity σ = 1.55 × 10-10 S m-1. C-U measurements confirm that the Au-PbPc interface does not form a Schottky barrier. At low temperatures the capacitance of Au-PbPc-Au devices is temperature insensitive, increasing rapidly above 300 K and saturating at about 400 K. Measurements of thermoelectric power confirm that semiconduction is p-type.
- Ahmad,Collins
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- Convenient and efficient method for the synthesis of phthalocyanines and metallophthalocyanines in task-specific 2-hydroxyethyl ionic liquids
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Tetramerization of substituted phthalonitriles in task-specific 2-hydroxylethyl-based imidazolium and ammonium ionic liquids at 100 °C gave corresponding phthalocyanines in moderate yield. Further the reaction of substituted phthalonitriles in the presence of transition-metal salts in ionic liquids gave the corresponding metallophthalocyanines. The 2-hydroxylethyl ammonium ionic liquids gave better yields of phthalocyanines than 2-hydroxylethyl imidazolium and nonhydroxyl functionalized ionic liquids. The isolation and separations of different phthalocyanines were accomplished by silica-gel column chromatography, and products were characterized by various spectroscopic techniques.
- Yadav, Kumar Karitkey,Poonam,Chauhan, Shive M. S.
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supporting information
p. 2797 - 2807
(2014/10/15)
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- Low-temperature synthesis of phthalocyanine and its metal complexes
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Conditions for synthesizing unsubstituted phthalocyanine and its metal complexes from phthalonitrile at low temperatures (0-50°C) are optimized. Phthalocyanine and phthalocyaninates are produced under these conditions using activated Rieke metals, metals on inert substrate, sources of soluble metals in the form of unstable metal complexes, zeolites, solid-phase electrosynthesis of phthalonitrile, and UV irradiation. The use of pyrophoric metals is found to be the most efficient due to a large number of defects in their structure favoring the initial stage of phthalonitrile cyclization on a metal matrix. The suggested mechanism of formation of phthalocyanine macrocycle assumes participation of metal agglomerates occurring in activated metals. Pleiades Publishing, Inc., 2006.
- Kharisov,Ortiz Mendez,Rivera De La Rosa
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p. 617 - 631
(2008/10/09)
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- Use of elemental metals in different grade of activation for phthalocyanine preparation
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Synthesis of non-substituted metal phthalocyaninates starting from phthalonitrile in various non-aqueous solvents in presence of a series of elemental metals in different grade of activation is described. Synthesis of non-substituted metal phthalocyaninates starting from phthalonitrile in various non-aqueous solvents in presence of a series of elemental metals in different grade of activation is described. Special attention is paid to phthalocyanine formation at relatively low temperatures (0-50°C). In case of use of various forms of activated and non-active nickel, it is shown that its most active form causes rapid PcNi formation at 0-25°C without addition of CH 3ONa.
- Kharisov,Coronado, C.E. Cantú,Cerda, K.P. Coronado,Méndez, U. Ortiz,Guzmán, J.A. Jacobo,Patlán, L.A. Ramírez
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p. 1269 - 1272
(2008/10/09)
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- SYNTHESIS OF METALLOPHTHALOCYANINES FROM PHTALONITRILE WITH STRONG ORGANIC BASES
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Several metallophthalocyanines (MPc: M=Ni(II), Co(II), Zn(II), Pb(II), Fe(II), Sn(II), Cd(II), Mg(II), and Mn(III)) were obtained by heating phthalonitrile with metal salts in alcohols in the presence of 1,8-diazabicycloundec-7-ene.Metal acetylacet
- Tomoda, Haruhiko,Saito, Shojiro,Shiraishi, Shinsaku
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p. 313 - 316
(2007/10/02)
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