Platinum phthalocyanine structure

The macrocyclic phthalocyanine ligand will form a complex Pt(phthalocyanine).1106 The crystal structure shows two polymorphs present because of molecular packing.1107 The platinum is in a square planar coordination geometry with a mean Pt—N distance of 1.98 A. The complex can be partially oxidized with iodine to give conducting mixed valence solids.1108 Eighteen fundamental and overtone combination bands are observed in the resonance Raman spectrum of platinum phthalocyanine, and from this data the symmetry of the excited singlets are found to be Dy.. Qlv or D2.1109... 

Figure 8a. The structure of platinum phthalocyanine. Electron density map of the molecule projected on a plane inclined at angle of 26.5 to the plane of the molecule.

Phthalocyanine was discovered by accident in 1907 when Braun and Tchemiac isolated a small amount of blue precipitate after heating o-cyanobenzamide in alcohol [41]. The chemical structure of phthalocyanine was established by Robertson and co-workers who reported the X-ray single crystal structures of nickel phthalocyanine, copper phthalocyanine and platinum phthalocyanine [42-45]. Phthalocyanines show intense... 

As is the case of tetrasubstituted phthalocyanines, a mixture of four structural isomers is obtained if the 5,6-substituents of isoindolinediimine are different. For example, 5-ethoxy-6-octyl-oxyisoindolinediimine, when treated with platinum(II) chloride in refluxing 2-(dimethylamino)-ethanol under nitrogen for 12 hours, yields a mixture of the corresponding isomeric piatinum(II) phthalocyanines in a yield of 28 %.117... 

Protactinium-233 and neptunium-239 diphthalocyanines are prepared from the corresponding thorium-232 and uranium-238 diphthalocyanines by element transformation [6]. The existence of Pa and Np di-Pcs is proven by repeated sublimation of the irradiated parent compounds using platinum gauze to retain the impurities. Neptunium di-Pc is also synthesized on the tracer scale from irradiated uranium metal, using the normal synthetic method for uranium di-Pc (Example 29) [6], Other actinide phthalocyanines are reported [107-114], Their structures, as well as those of 200 metal phthalocyanines and their derivatives, are classified in an excellent recent review [115]. More recent experimental data on actinide phthalocyanines are absent in the available literature. 

The insolubilities of phthalocyanines made their analysis difficult and it took some time before a satisfactory structure was elucidated. Initial work was undertaken by the Linstead group at Imperial College in the 1930s that culminated in a series of six back to back papers published in 1934 [14], It was also Linstead who named the compounds in recognition of their synthesis from phthalic anhydride and similarity to the blue cyanine dyes. Definitive characterization of the nickel, platinum and copper phthalocyanine complexes, together with the metal-free compound, was revealed in 1935 following the publication of their X-ray structures by Robertson [15] the copper and metal-free compounds are illustrated in Fig. 7.5. 

Robertson JM (1935) An X-ray study of the structure of the phthalocyanines. Part I. The metal-free, nickel, copper, and platinum compounds. J Chem Soc 615-621... 

Honigman, B Lenne, H. U. and Schrddel, R. (1965). Relations between the structures of the modifications of the platinum and copper phthalocyanines and some chloride derivatives. Z. Kristallogr, 122, 185-205. [268]... 

Beevers, C. A., and Lipson, H. Crystal structure of copper sulphate pentahy-drate, CuS04-5H20. Proc. Roy. Soc. (London) A146, 570-582 (1934). Robertson, J. M. An X-ray study of the structure of the phthalocyanines. Part I. The metal-free, nickel, copper and platinum compounds. J. Chem. Soc. (London) 615-621 (1934). 

The compound phthalocyanine, C32H18N8, is of exceptional interest on chemical grounds in that in combination with the metals Be, Mn, Fe, Co, Ni, Cu and Pt it forms derivatives of composition C32H36N8M of quite extraordinary stability the copper compounds, for example, sublimes without decomposition at 580 °C. The structure analysis reveals that the parent metal-free substance and all these derivatives (except that of platinum) are isomorphous and have unit... 

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