Phthalocyanine structure

Phosphorus phthalocyanine was described in 1981.161 However, recent investigations point to the fact that the originally described compound did not have a phthalocyanine structure.162... 

In addition to nonheme iron complexes also heme systems are able to catalyze the oxidation of benzene. For example, porphyrin-like phthalocyanine structures were employed to benzene oxidation (see also alkane hydroxylation) [129], Mechanistic investigations of this t3 pe of reactions were carried out amongst others by Nam and coworkers resulting in similar conclusions like in the nonheme case [130], More recently, Sorokin reported a remarkable biological aromatic oxidation, which occurred via formation of benzene oxide and involves an NIH shift. Here, phenol is obtained with a TON of 11 at r.t. with 0.24 mol% of the catalyst. 

In 1929, Linsted obtained samples of this complex from ICI chemists (Scottish Dyes Ltd was now owned by ICI). ICI had developed two routes leading to the phthalocyanine iron complex. One method started from phthalic anhydride, iron, and ammonia, while the second pathway proceeded from phthalimide, iron sulfide, and ammonia. In 1933/34, elucidation of the phthalocyanine structure was credited to Linstead. The corresponding copper and nickel phthalocyanines had been prepared in the meantime. ICI introduced the first Copper Phthalocyanine Blue to the market as early as 1935, and the Ludwigshafen subsidiary of the IG Farben-industrie followed suit with a corresponding product. 

Urea acts not only as an ammonia source but also forms decomposition products, such as biuret and higher condensation products. 14C labeling has indicated that the carbon atom of the urea molecule is not incorporated into the phthalocyanine structure. Employing a phthalic anhydride molecule bearing one radioac-tively labeled carbonyl function affords labeled copper phthalocyanine and phthalimide (as a side product), while the liberated carbon dioxide was found not to show any radioactivity. Labeled carbon dioxide, on the other hand, has been obtained in corresponding experiments using 14C labeled urea. 

There is an interesting technique which makes it possible to introduce carboxylic acid groups into a copper phthalocyanine structure by an economical route. Carrying out the phthalic anhydride/urea process in the presence of a small amount of trimellitic acid or another benzene polycarboxylic acid will afford a car-boxylated pigment. 

Flocculation may likewise be prevented through partial introduction of dialkyl-aminomethylene groups into the aromatic ring system of the copper phthalocyanine molecule. The copper phthalocyanine structure tightly attaches the basic groups... 

The chemistry of pyrroles also includes complex pyrrole systems, por-phirin, and phthalocyanine structures such as haemin, chlorophill, hemoglobin, bile pigments, cytochromes, and vitamin Bi2. 

Compounds with the molecular formula (CgH4N2)3BX, where X = F or Cl, have been previously isolated from reactions of halogenoboranes and phthalodinitrile. The structure of the chlorine compound has now been determined and shows a phthalocyanine-like structure (31).179 The system is bowl-shaped, in contrast to the planar phthalocyanine structure. The boron atom is co-ordinated to three N atoms (at 1.467 A, i.e. short) and one Cl (1.863 A). The tt-electrons in the 14-membered ring form a quasi-aromatic conjugated Tr-system. 

In order to determine the extent to which the procedure employed by Griffith and co-workers generates phthalocyanine structures, both the amount of unreacted starting material and of phthalocyanine present in the reaction mixture need to be analytically determined. To this end, compounds VI and VII, which serve as models for I and II, were prepared by scheme 1. 

Other wonderful shapes can also be found. The metal phthalocyanine structure with its bridging pyrazine units, shown in Scheme 4, resembles a shiskabob. The metal and pyrazine chain forms the "skewer" which "pierces" the phthalocyanine groups. A braided struc-ture is also represented in Scheme 4. 5-Phenyltetrazolate reacts with metals from all three transition metal series to give the loops shown. The Ni(II) and Fe(II) adducts give extremely viscous aqueous solutions from which both flexible sheets and threads have been made. ... 

Tetraguanidinium-modified phthalocyanines recognize DNA containing G-quadruplex (G4) sequences. The phtha-locyanine DNA adducts efficiently transfect into cells. The planar phthalocyanine structures are capable of intercalation into the DNA quadruplex loop and bind to the peripheral phosphates. Nonmetallated 63 stabilizes both the parallel and antiparallel forms of G4-DNA. The Zn-metallated derivative 64 selectivity stabilizes parallel G4-DNA. 

In the design of complex phthalocyanine structures with specific properties, substituted phthalocyanines play an important role. 4-Nitrophthalodinitrile 1484, a key starting material in the synthesis of tetranitrophthalocyanine 1485, is produced from 4-nitrophthalamide 1483 by dehydration with triflic anhydride in 91% yield [1126]. 

Appleby AJ, Savy M, Caro P (1980) The role of transition element multiple spin crossover in oxygen transport and electroreduction in porphyrin and phthalocyanine structures. J Electroanal Chem 111 91-96... 

Poor sotulnlity, (chloconaphthalene is a good solvent for phthalocyanines). Structured abs in the... 

Phthalocyanine compounds contain macrocyclic conjugated pi-electron systems and metal ions in the central void. These phthalocyanine structures are very similar to porphyrins, one of the most important compounds in biochemistry. Accordingly, phthalocyanine compounds are expected to facilitate interesting catalysis and multielectron processes. Almost all metal and semi-metal ions can be incorporated in the central void of the phthalocyanine molecule, and the characteristics of such phthalocyanine compounds can be modified by the metal ions. About seventy metals are known to incorporate in the phthalocyanine molecule. 

Metal-containing polymers exist in a plethora of wonderful shapes and structures including rods, sheets, and coils. There are a number of interesting structural classes of polymers known as stacked systems. These include both the shish-kebab type and the polydecker sandwich-type structures. A metal phthalocyanine structure with bridging pyrazine units (51) resembles a shish-kebab, in which the metal-pyrazine chain represents the skewer. ... 

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