Porphyrins hydroporphyrins

The tetramerization of suitable monopyrroles is one of the simplest and most effective approaches to prepare porphyrins (see Section 1.1.1.1.). This approach, which is best carried out with a-(hydroxymethyl)- or ot-(aminomethyl)pyrroles, can be designated as a biomimetic synthesis because nature also uses the x-(aminomethyl)pyrrole porphobilinogen to produce uroporphyrinogen III. the key intermediate in the biosynthesis of all kinds of naturally occurring porphyrins, hydroporphyrins and corrins. The only restriction of this tetramerization method is the fact that tnonopyrroles with different -substituents form a mixture of four constitutionally isomeric porphyrins named as porphyrins I, II, III, and IV. In the porphyrin biosynthesis starting from porphobilinogen, which has an acetic acid and a propionic acid side chain in the y6-positions, this tetramerization is enzymatically controlled so that only the type III constitutional isomer is formed. 

Porphyrins, Hydroporphyrins, Azaporphyrins, Phthalocyanines, Corroles, Corrins and Related Macrocycles... 

Mashiko, T. Dolphin, D. Porphyrins, hydroporphyrins, azaporphyrins, phthalocyanines, corroles, corrins and related macrocycles. In Comprehensive Coordination Chemistry Wilkinson, G., Gillard, R. D., McCleverty, J. A., Eds. Pergamon Oxford, 1987, Vol. 2, Chapter 21.1. 

Refs. [i] Mashiko T, Dolphin D (1987) Porphyrins, hydroporphyrins, azaporphyrins, phthalocyanines, corroles, corrins and related macrocy-... 

The iron porphyrins and related compounds constitute an extremely important class of coordination complex due to their chemical behaviour and involvement in a number of vital biological systems. Over recent years a vast amount of work on them has been published. Chapter 21.1 deals with the general coordination chemistry of metal porphyrins, hydroporphyrins, azaporphyrins, phthalocyanines, corroles, and corrins. Low oxidation state iron porphyrin complexes are discussed in Section 44.1.4.5 and those containing nitric oxide in Section 44.1.4.7, while a later section in this chapter (44.2.9.2) is mainly concerned with iron(III) and higher oxidation state porphyrin complexes. Inevitably however, a considerable amount of information on iron(II) complexes is contained in that section as well as in Chapter 21.1. Therefore in order to prevent excessive duplication, the present section is restricted to highlighting some of the more important aspects of the coordination chemistry of the iron(II) porphyrins while the related unusually stable phthalocyanine complexes are discussed in the previous section. 

Porphyrins, hydroporphyrins, azaporphyrins, phthalocyanines, corroles, corrins, and related macrocycles were discussed in CCC (1987).144 The octaethylporphyrin complexes of scandium were also previously mentioned in CCC (1987).1 The octaethylporphyrin (oep) scandium chloride complex (oep)ScCl, prepared by the reaction of the dilithium porphyrin with ScCl3(thf)3, has proved... 

Liu, Y, C. DeSilva, and M.D. Ryan (1997). Electrochemistry of nitrite reductase model compounds. 6. Voltammetric and spectroelectrochemical studies of iron(II) nitrosyl complexes with porphyrins, hydroporphyrins and porphinones. Inorg. Chim. Acta 258, 247-255. 

Calculations on the Excited States of Porphyrin, Hydroporphyrins, Tetrazaporphyrins, and Metalloporphyrins. 

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