Zirconium phthalocyanine

Zirconium phthalocyanine (PcZrCl2) is prepared in a high-boiling solvent like 1-chloro-naphthalene using phthalonitrile and zirconium(IV) chloride.222 If the reaction is carried out without solvent, chlorination of the phthalocyanine ring may occur as a side reaction.223,224... 

Zirconium(IV) bis (phthalocyanine) (Pc2Zr) can be prepared from phthalonitrile223 or isoindolinediimine225 and zirconium(IV) chloride. 

Bis(phthalocyanines) are also accessible by the reaction of isoindolinediimine and suitable metal compounds. For example, zirconium(IV) chloride when treated with isoindolinediimine in refluxing quinoline under a nitrogen atmosphere for 2 hours gives a zirconium(IV) bis(phthalocyanine) complex. 

The reduction can also be performed electrochemically. For example, bis(triphenylphos-phane)iminium [trichlorozirconium(IV) phthalocyanine] can be reduced (dichloromethane, reflux, platinum electrode, 2 V, cathodic reduction) to a zirconium(III) species.222... 

The phthalic anhydride/urea process may also be employed to convert tetra-chloro phthalic anhydride to green copper hexadecachloro phthalocyanine by condensation. In this case, titanium or zirconium dioxides, particularly in the form of hydrated gels, are used instead of the molybdenum salts which are used in the phthalic anhydride process [23]. There is a certain disadvantage to the fact that the products lack brilliance and require additional purification. 

Copper Perbromo Phthalocyanine Green may also be obtained from tetra-bromo phthalic anhydride by the phthalic anhydride/urea process in the presence of titanium or zirconium catalysts. This route has not yet been introduced on a commercial scale. 

The metallophthalocyanines which have found application as elecfiochromes are mainly the rare earth derivatives, especially lutetium, and second row fiansition metals such as zirconium and molybdenum. Synthesis of these molecules follows the fiaditional routes, e.g. condensation of 1,2-dicyanobenzene with a metal acetate in a high boiling solvent (see Chapter 2). These compounds have structures in which the rare earth element is sandwiched between two phthalocyanine rings, e.g. zirconium bisphthalocyanine (1.92 M = Zr) and lutetium bisphthalocyanine (192 M = Lu), the latter protonated on one of the meso N atoms to balance the charge. 

Syntheses of MPc from phthalodinitrile or phthalic anhydride in the presence of urea are the two most important laboratory and industrial methods. They were also used originally by Linstead et al. [8,9], This procedure allows the production of many phthalocyanine compounds [35-37], Catalysts such as boric acid, molybdenum oxide, zirconium and titanium tetrachloride, or ammonium molybdate are used to accelerate the reaction and improve the yield [36,37], Ammonium molybdate is especially effective. Reaction is carried out either in a solvent or by heating the solid components. When metal chlorides and phthalodinitrile are used as starting materials, the reaction products are partially chlorinated (e.g.,7). 

M. E. Nino, S. A. Giraldo, E. A. Paez-Mozo, Olefin oxidation with dioxygen catalyzed by porphyrins and phthalocyanines intercalated in /-zirconium phosphate, J. Mol. Catal. A Chem. 175 (2001) 139. 

The particle surface of pigment Ti02 was treated with the oxides of aluminium, silicon and zirconium, and the surface of pigment Fe203 - with aluminium and silicon oxides. Pure phthalocyanine pigment - p-CuPc was used in the work. 

Equations (II) to (IX) illustrate basic methods of preparation, but many variations are used, particularly in industry, to obtain an economic yield. Phthalic acid, phthalamide, phthalimide, and phthalic anhydride, together with urea, are often used instead of phthalonitrile, and catalysts such as ammonium molybdate or zirconium tetrachloride may be employed (249, 251, 269). The reaction between phthalonitrile and metals (finely divided or acid-etched) is usually very vigorous at 250°-300°C, sufficient heat being generated to maintain the reaction temperature. This is an illustration of the ease with which the phthalocyanine skeleton is formed. Even more surprising are the observations that palladium black (118) and gold (189) will dissolve in molten phthalonitrile. Reaction (III) between phthalonitrile and a finely divided metal, metal hydride, oxide, or chloride is perhaps the most generally employed. For the unstable phthalocyanine complexes such as that of silver (11), the double decomposition reaction... 

Both zirconium and hafnium tetrachlorides react with phthalonitrile at 170°C to give products which when crystallized from sulfuric acid were formulated as dihydroxyzirconium(IV) and -hafnium(IV) chloro-phthalocyanine dihydrates (284). Once again their formulation as oxy derivatives, perhaps polymeric, seems more reasonable. A sulfonated hafnium phthalocyanine has also been reported (119). 

Cartoni et al. [88] studied perspective of the use as stationary phases of n-nonyl- -diketonates of metals such as beryllium (m.p. 53°C), aluminium (m.p. 40°C), nickel (m.p. 48°C) and zinc (liquid at room temperature). These stationary phases show selective retention of alcohols. The retention increases from tertiary to primary alcohols. Alcohols are retained strongly on the beryllium and zinc chelates, but the greatest retention occurs on the nickel chelate. The high retention is due to the fact that the alcohols produce complexes with jS-diketonates of the above metals. Similar results were obtained with the use of di-2-ethylhexyl phosphates with zirconium, cobalt and thorium as stationary phases [89]. 6i et al. [153] used optically active copper(II) complexes as stationary phases for the separation of a-hydroxycarboxylic acid ester enantiomers. Schurig and Weber [158] used manganese(ll)—bis (3-heptafiuorobutyryl-li -camphorate) as a selective stationary phase for the resolution of racemic cycUc ethers by complexation GC. Picker and Sievers [157] proposed lanthanide metal chelates as selective complexing sorbents for GC. Suspensions of complexes in the liquid phase can also be used as stationary phases. Pecsok and Vary [90], for example, showed that suspensions of metal phthalocyanines (e.g., of iron) in a silicone fluid are able to react with volatile ligands. They were used for the separation of hexane-cyclohexane-pentanone and pentane-water-methanol mixtures. 

Names Cloisite Nanofrl Phthalocyanine copper-alpha- or betaform Titanium carbide, WS2 nanotubes Zinc oxide nanoparticles Zirconium carbide... 

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