Iron-phthalocyanine

PhdialocyaiiiQe/3 74-5 J-, C22H gNg, compounds have found widespread acceptance ia a variety of applications. The discovery of iron phthalocyanine [132-16-1] and the elucidation of its stmcture led to the commercial appHcation of copper phthalocyanine [147-14-8] (1). 

Air oxidation of dyestuff waste streams has been accompHshed using cobalt phthalocyanine sulfonate catalysts (176). Aluminum has been colored with copper phthalocyanine sulfonate (177,178). Iron phthalocyanine can be used as a drier in wood oil and linseed oil paints (179). 

CNTs were also synthesized at lower temperatures starting from some metal phthalocyanines [18]. Nickel-, cobalt- and iron-phthalocyanines were deposited in vacuum and CNTs were grown perpendicularly on a quartz substrate at 700 and 800°C at relatively high yield. At the base of the nanotubes, a cluster of metal... 

Chromium(II) phthalocyanine (PcCr) is prepared from phthalonitrile and hexacarbonylchro-mium(O) in 1-chlornaphthalene.234 PcCr(OAc) is prepared from phthalonitrile and chro-mium(III) acetate without solvent235 or in nitrobenzene starting from chromium(II) acetate236 under reflux. Chromium(lll) phthalocyanine also forms /t-oxo dimeric complexes,237 which are more common with iron phthalocyanines. 

In /<-oxo dimers two phthalocyanines are bridged by an oxygen atom. Iron phthalocyanines, especially, tend to form this kind of compound, e.g. 13. 

Previous studies by Sorokin with iron phthalocyanine catalysts made use of oxone in the oxidation of 2,3,6-trimethylphenol [134]. Here, 4 equiv. KHSO5 were necessary to achieve full conversion. Otherwise, a hexamethyl-biphenol is observed as minor side-product. Covalently supported iron phthalocyanine complexes also showed activity in the oxidation of phenols bearing functional groups (alcohols, double bonds, benzylic, and allylic positions) [135]. Besides, silica-supported iron phthalocyanine catalysts were reported in the synthesis of menadione [136]. 

A variety of aUcenes can be converted to aziridines with PhINTs in good yields (48-90%) using iron phthalocyanine as catalyst (Scheme 24) [79]. It is noteworthy... 

Iron phthalocyanine is an efficient catalyst for intermolecular amination of saturated C-H bonds. With 1 mol% iron phthalocyanine and 1.5 equiv. PhlNTs, amination of benzylic, tertiary, and ally lie C-H bond have been achieved in good yields (Scheme 31). With cyclohexene as substrate, the allylic C-H bond amination product was obtained in 75% yield, and the aziridination product was found in minor amount (17% yield) [79]. 

Baranton S, Coutanceau C, Roux C, Hahn F, Leger JM. 2005. Oxygen reduction reaction in acid medium at iron phthalocyanine dispersed on high surface area carbon substrate tolerance to methanol, stability and kinetics. J Electroanal Chem 577 223-234. 

Lalande G, Faubert G, Cote R, Guay D, Dodelet JP, Weng LT, Bertrand P. 1996. Catalytic activity and stability of heat-treated iron phthalocyanines for the electroreduction of oxygen in polymer electrolyte fuel cells. J Power Sources 61 227-237. 

Figure 30.5. Proposed oxidation mechanism of glucoside unit by iron phthalocyanine-H202 system.

A practical method of modification of polysaccharides by clean oxidation using H2O2 as oxidant and cheap iron phthalocyanine as catalyst has been developed. Since no acids, bases or buffers and no chlorinated compounds were used, a pure product can be recovered without additional treatment. Importantly, this flexible method provides materials with a wide range of DScho and DScooh just by an appropriate choice of the reaction conditions. Oxidized polysaccharides thus obtained possess various, tailormade hydrophihc/hydrophobic properties which have been tested successfully in cosmetic and other apphcations. 

The heterogeneous catalytic system iron phthalocyanine (7) immobilized on silica and tert-butyl hydroperoxide, TBHP, has been proposed for allylic oxidation reactions (10). This catalytic system has shown good activity in the oxidation of 2,3,6-trimethylphenol for the production of 1,4-trimethylbenzoquinone (yield > 80%), a vitamin E precursor (11), and in the oxidation of alkynes and propargylic alcohols to a,p-acetylenic ketones (yields > 60%) (12). A 43% yield of 2-cyclohexen-l-one was obtained (10) over the p-oxo dimeric form of iron tetrasulfophthalocyanine (7a) immobilized on silica using TBHP as oxidant and CH3CN as solvent however, the catalyst deactivated under reaction conditions. 

Since iron phthalocyanine complexes can be activated and stabilized by a chlorine ring substitution (12), the activity of iron hexadecachlorophthalocyanine (7b) immobilized on silica was examined for the synthesis of 4, 5, and 6 with TBHP as oxidant. 

The major types of complexes under intense investigation are the tetraden-tate Schiff base, for example, CoSalen, and phthalocyanine, for example, iron phthalocyanine complexes (Fig. 7.1).69... 

Catalysts from active carbon additionally activated with cobalt- or iron- phthalocyanines are also studied [7], The results show that at current densities up to 50 mA/cm2, the polarization of the air electrodes with catalyst from active carbon promoted with FePc is lower than that of the electrode with catalyst from active carbon promoted with CoPc. At higher current density the polarization of the electrode with catalyst from active carbon promoted with CoPc is lower, which is probably connected to the lower transport hindrances, due to the more favorable structure of this catalyst. 

A mild aerobic palladium-catalyzed 1,4-diacetoxylation of conjugated dienes has been developed and is based on a multistep electron transfer46. The hydroquinone produced in each cycle of the palladium-catalyzed oxidation is reoxidized by air or molecular oxygen. The latter reoxidation requires a metal macrocycle as catalyst. In the aerobic process there are no side products formed except water, and the stoichiometry of the reaction is given in equation 19. Thus 1,3-cyclohexadiene is oxidized by molecular oxygen to diacetate 39 with the aid of the triple catalytic system Pd(II)—BQ—MLm where MLm is a metal macrocyclic complex such as cobalt tetraphenylporphyrin (Co(TPP)), cobalt salophen (Co(Salophen) or iron phthalocyanine (Fe(Pc)). The principle of this biomimetic aerobic oxidation is outlined in Scheme 8. 

Fig. 1. Cyclic voltammetry of 7% w/w iron phthalocyanine, FePc dispersed on Vulcan XC-72 carbon, after a heat treatment at 280°C in a flowing inert atmosphere. The measurement was conducted with the material in the form a thin porous Teflon bonded coating in 1 M NaOH at 25°. Sweep rate 5 mV/s. (Reproduced with permission from ref. 3. Copyright 1985 Elsevier.)...

This material was prepared by the heat treatment of iron phthalocyanine dispersed on the carbon in an inert atmosphere at 280°C. 

Iron phosphate glasses, 12 585, 616 Iron phosphates, 18 839 Iron phosphating, 16 214-215 applications for, 16 215 Iron phthalocyanine, isolation of, 24 36 Iron(II) phthalocyanine, 14 547 Iron plating baths, 9 814t Iron porphyrin-catalyzed dye oxidation, 9 383-384... 

Table 3.1 Oxidation of starch in aqueous suspension with H2O2 in the presence of iron phthalocyanine.a> Effect of substrate/catalyst ratio.

The oxidation of starch in aqueous suspension with H202 in the presence of iron phthalocyanine gives both carboxylic and carbonyl groups (Table 3.1). The best yields were obtained with a molar ratio 12900/1 (0.0078 mol%), but the oxidation was still quite efficient with 0.0039 mol% of catalyst [25800 per anhydroglucose unit (AGU)/catalyst ratio]. The oxidized starch had almost the same final Fe-content as the initial potato starch. Still, the efficiency of this method in view of scaling up was limited by comparatively low activity and product isolation problems. 

Conjugated arylalkenes undergo ally lie amination on treatment with /V-phcnylhydro-xylamine under the influence of iron phthalocyanin, e.g. equation 71. The yields from aliphatic olefins are very poor 1-octene gives only 3% of the amine 193198. 

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