Metal-Schiff base phthalocyanine complex

Mitchell and Valero (1982, 1983) studied VO-phthalocyanine (VO-PC) and a Schiff base complex, VO-salen, as model vanadium compounds. The VO-PC provides a metal coordination environment comprised of four nitrogens, similar to the porphyrin. The benzo rings at the /3-pyrrolic positions contribute to enhanced aromaticity in the metal ligand. 

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... 

F. Bedioui, Zeolite-encapsulated and Clay-intercalated Metal Porphyrin, Phthalocyanine and Schiff-base Complexes as Models for Biomimetic Oxidation Catalysts an Overview. Coord. Chem. Rev., 1995, 144, 39—68. 

Complexes of metal + ligand + protein or DNA can also catalyze the Diels Alder cycloaddition or oxidations with hydrogen peroxide. Copper complexes bound to DNA catalyzed the Diels-Alder cycloaddition with up to 99% ee [15, 16], Cu(phthalocyanine) complexed to serum albumin also catalyzed the enantioselective (98% ee) Diels-Alder reaction, but only with very high catalyst loading (10 mol%) and only with pyridine-bearing dienophiles (presumably to complex the copper) [17]. Achiral Cr(III) complexes or Mn(Schiff-base) complexes inserted into the active site of apomyoglobin variants catalyzed the sulfoxidation of thio-anisole with up to 13 and 51% ee, respectively [18, 19]. A copper phenanthroline complex attached to the adipocyte lipid-binding protein catalyzed the enantioselective hydrolysis of esters and amides [20]. 

A connectivity of 1 is given for side chain metal-containing polymers as 1 in which the metal complex is connected via one bond to the main chain [11]. Additional examples for other connectivities are (Fig. 1-8) connectivity 2 in metal(yne)s 2 [12] connectivity 3 in arsenic(III) sulfide 3 connectivity 4 in a polymeric methyl rhenium oxide of the formula Ho.5[(CH3)o.92Re03] co 4 [13] or polymeric phthalocyanines 5 [14] connectivity 8 in lanthanide complexes of bis(tetradendate) Schiff base bridging ligands 6 [15]. 

Bedioui, F. (1995). Zeohte-encapsulated and clay-intercalated metal porphyrin, phthalocyanine and Schiff-base complexes as models for biomimetic oxidation catalysts—an overview. Coord. Chem. Rev. 144, 39-68. 

This chapter describes the synthesis and properties of a number of classes of polymers containing metal coordination complexes in their structures. These polymers are prepared by polymerization reactions of metal-containing monomers and through metal coordination reactions. Schiff base-containing polymers (5) were one of the earUest classes of coordination polymers examined. Polymers incorporating macro-cycUc porphyrins and phthalocyanines (7) in their backbones and sidechains are known to exhibit interesting optical and electrical properties. The best-studied classes of metal-containing polymers contain bipyridyl and other related units coordinated to metal ions (8). 

Many other types of polymer have been prepared which exhibit semiconductivity. All obey the equation a = a0exp — E/kT. These include xanthene polymers (109, 110), polymerized phthalocyanines (111, 112), epoxides and polydiketones (86, 113), polypentadienes (114), polydicyanoacetylenes (115), polyvinylferrocene and substituted ferrocene (116, 117, 118, 119), polymeric complexes of tetracyanoethylene and metals (120), poly(vinyl chloride) and poly(vinylidene chloride) (121), polyvinylene and polyphenylene (122) and poly(Schiff s bases) (123, 124). 

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