Phthalocyanines polynuclear

Reaction of the manganese tropocoronand complex [Mn(tc-5,5)(NO)] with [Fe(tc-5,5)] results in complete transfer of the NO to the [Fe(tc-5,5)]. Other nitric oxide complexes appear in the sections on nitroprusside (Section S.4.2.2.6 above), on phthalocyanines (Section 5.4.3.7.4 above), and on polynuclear iron-sulfide complexes (Roussin s salts Section 5.4.5.9.2 below) Fe-por-phyrin-NO redox chemistry has been mentioned in Section 5.4.3.7.2 above. 

The reason of why such reactions are discussed separately stems from the fact that metal-metal (both a direct or a bridge mediated) interaction causes certain specific properties of polynuclear complexes, and cannot be, therefore taken as a simple sum of their independent mononuclear constituents. A particular case is some phthalocyanine dimers in which the monomers are bound via a close k-tz system contact of the phthalocyanine ligands. Such dimers are included in this Section too in spite of the fact that there is neither a direct metal-metal bond nor a bridge connection. 

A series of articles is devoted to the preparation of Pc complexes from metal alloys ([21a] and references cited therein). The most important advantage of the alloys use is an easier reaction between phthalonitrile and the alloy s component(s), due to a concentration gradient of metal particles on the alloy surface. As a consequence of such an interaction, it is possible to obtain polynuclear phthalocyanines and separate the alloy [21a]. This relatively new and intriguing field in Pc research should undoubtedly be taken into account. Another nonstandard technique for metal phthalocyanine production is the use of microwave irradiation under solvent-free conditions (for more details see Sec. 3.5). In particular, this method was used for obtaining phthalocyanine derivatives of Ru, Rh, Pt, and Pt [21b], Zn, Mg, Co, and Cu [21c], or Si [21d]. 

In this way, alkoxides, glycolates, catecholates, carboxylates, or Schiff base complexes have been obtained.37,38 Other metal chelates have been synthesized by electro-oxidation of the bare metal electrode phosphido, azolates, phthalocyanines, semicarbazides, Schiff bases, etc.37 In addition to the syntheses of monometallic complexes, electrochemistry has been proven to yield polynuclear complexes by using assembling or multidentate ligands.37... 

The formation of dimetal face-to-face macrocycles can effectively promote a 4-electron transfer pathway from oxygen to water. For example, such catalysts include dicobalt face-to-face porphyrins [15], and pillared dicobalt cofacial porphyrins [16], as well as other binuclear and polynuclear Co phthalocyanines [17]. In this catalyst, two Co centers can provide two adsorption sites for O2 to form a bridge adsorption, facilitating a 4-electron transfer process, as suggested by Anson et al. [18, 19] ... 

Tai C, Jiang G, Liu J, Zhou Q, Liu J (2005) Rapid degradation of bisphenol A using air as the oxidant catalyzed by polynuclear phthalocyanine complexes under visible light irradiation. J Photochem Photobiol A 172 275-282... 

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