Diphthalocyanine metal complexes and their analogues

Abstract

<jats:p> The present overview deals with ditetrapyrrolic macrocycles, mainly diphthalocyanine systems, of the following three classes: (a) sandwich-type molecules (I); (b) metal-metal bonded systems (II); (c) single-atom bridged dimers (III). The available information focuses on the structural and electronic features, redox properties and partial oxidation. Practical applications, e.g. electrochromic devices, molecular metals, liquid crystals, non-linear optics, etc., make these classes of complexes particularly attractive and promising materials. The bonding mechanism and the structural, magnetic, conductive and optical properties of these systems are elucidated by density functional calculations. </jats:p>

Dedication to Professor Claudio Ercolani on the Occasion of his 75th Birthday

“…Professor Ercolani has published more than 120 scientific works including 8 book chapters and review articles. [1][2][3][4][5][6][7][8] Among other research items, he has developed especially intense and successful scientific activity and published 90 research articles in the field of tetrapyrrolic macrocycles, devoting his attention to: 1) Synthesis and characterization of new monophthalocyanine complexes. [9][10][11][12][13][14] 2) Interaction of metal phthalocyanines with small molecules (NO, CO, O 2 ) and N-bases.…”

Metal- and Ligand-Centered Monoelectronic Oxidation of μ-Nitrido[((tetraphenylporphyrinato)manganese)(phthalocyaninatoiron)], [(TPP)Mn−N−FePc]. X-ray Crystal Structure of the Fe(IV)-Containing Species [(THF)(TPP)Mn−N−FePc(H2O)](I5)·2THF

“…Both species, formally mixed-valence Fe(III)-Fe(IV) entities, and, indeed, characterized by the presence of iron atoms sharing the same oxidation state between +3 and +4, i.e., Fe(+3.5), have allowed the synthesis, through monoelectronic oxidation, of several µ-nitrido species containing Fe(IV)-Fe(IV) couples, i.e., high valent iron. 2,3 PcRu-N-RuPc has also been reported, 4 the only species known to involve a second row transition metal. The first and so far unique member reported of the class (L)M-N-M(L′) was the mixed-ligand Fe-Fe complex (TPP)Fe-N-FePc, 5,6 again, noteworthy, characterized by the presence of two Fe centers in an intermediate oxidation state (+3.5), and capable of undergoing monoelectronic oxidation with formation of an Fe(IV) containing species of formula [(THF)(TPP)Fe IV -N-Fe IV Pc(H 2 O)](I 5 )‚2THF, structurally elucidated by single-crystal X-ray work.…”

Unusual Cyan-Purple Electrochromism of Sandwich Phthalocyaninates Observed on the Example of µ-Carbido Diruthenium(IV) Complex

“…[37] The architecture of sandwich REE complexes with Pc ligands is based on misfit between the size of the macrocyclic cavity and the large ionic radii of metal ions, while these ions can coordinate the second macrocycle due to the large coordination numbers. However, the sandwich architecture can be obtained by an alternative approach [38] -via binding of monophthalocyaninates with nonmetal bridging atoms -[MPc] 2 (m-X), where X = C, N, O (Figure 1a). Metal centers in such complexes include tri-and tetravalent metals like Al, Mn, Fe, Ru, etc., and tetravalent metalloids like Si and Ge bearing additional anionic groups.…”