Porphyrin complexes overview

This review is intended to give an overview of the recent progress in the area of the formation of metalloporphyrins (the mechanism of the direct metalation reaction) and their reactions with small molecules (CO, NO, H20, 02). Although the emphasis is on less studied examples, a selection of recent results on iron (II) porphyrin complexes with CO and NO is also included. 

In some cases where a reaction involving a radical species occurred within cobalt porphyrin complexes, it has been possible to trap transient cobalt porphyrin hydride species. This was indeed observed during the synthesis of organocobalt porphyrin that resulted from the reaction of cobalt(n) porphyrin and dialkylcyanomethylradicals with alkenes, alkynes, alkyl halides, and epoxide. A transient hydride porphyrin complex was also involved in the cobalt porphyrin-catalyzed chain transfer in the free-radical polymerization of methacrylate. The catalytic chain transfer in free-radical polymerizations using cobalt porphyrin systems has been extensively investigated and will not be treated in this section. Gridnev and Ittel have published a comprehensive overview of the catalytic chain transfer in free-radical polymerizations. ... 

We first give an overview of the general features of these various compounds and the means by which they have been characterized (Sect. 4.1). The individual classes of compounds are then described, beginning with the dionedioximates (Sect. 4.2), followed by the most important class, the prophyrinic complexes (Sect. 4.3), and then, briefly, by the dithiolates and porphyrin-like analogues (Sect. 4.4). 

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. 

An overview of the thermodynamic principles governing self-assembly in solution, with particular reference to multiporphyrin architectures, is presented by Gianfranco Ercolani in the fifth chapter. The topic is discussed in order of increasing complexity, from simple acyclic assembhes to multi-cyclic assemblies. The principles are illustrated by selected examples of metal-mediated assemblies of porphyrins, many of which have been described in the previous chapters. 

D.K.R Ng, J. Jiang, K. Kasuga and K. Machida conclude this volume with an overview of rare-earth and actinide half-sandwich tetrapyrrole complexes. When tetrapyrrole molecules, such as porphyrins or phthalocyanines, are reacted with the rare earths and actinides, they are split in half, forming the half-sandwich complexes because the metal atoms are larger than the core size of the macrocyclic ligands. They also can form sandwich-type complexes in which the metal centers are sandwiched between the macrocycles. However, this chapter is devoted to the former class of compounds. Ng and co-workers discuss the synthesis, structure, and spectroscopic and electrochemical properties of half-sandwich complexes of porphyrins and phthalocyanines. The authors... 

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. 

The interfacial reactivity of metalloporphyrins and chlorins is critically determined by their specific adsorption at the liquid/liquid junctions. The affinity of the water-soluble porphyrins for these interfaces is associated with their complex solvation structure arising from the hydrophobic central ring and peripheral ionisable groups. This chapter will also feature a brief overview on recent studies of the molecular organisation of water-soluble porphyrins as probed by a variety... 

This chapter gives an overview on the chemistry of tetravalent lanthanide compounds, especially those of tetravalent cerium. Following a brief introduction, it covers the tetrahalides, dioxides, and other lanthanides(IV) salts. Coordination compounds of cerium in the oxidation state +4 include halogeno complexes and complexes of oxo acids, /3-diketonates and related Schiff-base complexes, as well as porphyrinates and related complexes. 

While major advances in the area of C-H functionalization have been made with catalysts based on rare and expensive transition metals such as rhodium, palladium, ruthenium, and iridium [7], increasing interest in the sustainability aspect of catalysis has stimulated researchers toward the development of alternative catalysts based on naturally abundant first-row transition metals including cobalt [8]. As such, a growing number of cobalt-catalyzed C-H functionalization reactions, including those for heterocycle synthesis, have been reported over the last several years to date (early 2015) [9]. The purpose of this chapter is to provide an overview of such recent advancements with classification according to the nature of the catalytically active cobalt species involved in the C-H activation event. Besides inner-sphere C-H activation reactions catalyzed by low-valent and high-valent cobalt complexes, nitrene and carbene C-H insertion reactions promoted by cobalt(II)-porphyrin metalloradical catalysts are also discussed. 

The cyclopropanation of olefins of various electronic properties by diazo compounds in the presence of complexes of group 9 metals with porphyrins has been systematically overviewed. " ... 

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