Porphyrinic metal complex

Dendrimers with a Porphyrin Metal Complex as a Core.212... 

Porphyrin-metal complexes are natural mimetic substances that have attracted much attention during the past decade. The epoxidation of olefins by porphyrin complexes proceeds well, but with only modest enantioselectivity. As this area of research is growing, description of a few selected publications may be useful.96... 

Chiral porphyrin metal complex catalysts have also received much attention. In this situation, the flat, symmetrical porphyrin structure must be modified dramatically in order to incorporate dissymmetry. This has been achieved through strapping techniques. " Some examples are shown in Figure 11.7. 

Table 18.1 Typical photoinduced hydrogen evolution systems using porphyrin metal complexes...

Photoinduced Hydrogen Evolution with Water-soluble Viologen-linked Cationic Porphyrin Metal Complexes and Hydrogenase... 

In this chapter, we described some artificial photosynthesis systems that employ porphyrin metal complexes to photoinductively evolve hydrogen. Although further development is required, the photoinduced hydrogen evolution systems described in this chapter will likely be useful in the conversion of solar energy to chemical energy. 

Photoinduced Hydrogen Evolution with Viologen-linked Porphyrin Metal Complexes... 

P otoinduced Hydrogen Evolution with Porphyrin Metal Complexes 3 1... 

Covalent coupling A pre-existing metal complex is coupled covalently with den-drons and is thus surrounded by a dendritic shell. Appropriate examples are the redox-active metallodendrimers of Kaifer et al. [117] or the dendritic porphyrin/ metal complexes prepared and characterised by Diederich et al. [118] and Aida et al. [119]. 

Fig. 8.7 Dendritic porphyrin-metal complex (according to Diederich et al.)...

Figure 21 Non-porphyrin metal complex as new prosthetic groups for Mb.

Figure 1.30 Dipolar porphyrin metal complexes with large /3 values...

What is most needed now, in the opinion of the author, is a detailed model rationalizing the interactions between the in-plane metal-nitrogen bonds and the n and d orbitals of the porphyrins and axial ligands, as well as the d orbitals of the metals that do not lie in this plane. Such an insight should account for the main influence of the three partners in the porphyrin metal complexes on each other many more exciting experiments could then be planned. 

Many oxygenases contain the heme prosthetic group which usually is protoheme IX (Scheme X1.3). For example, similarly to other porphyrin metal complexes, four coordination sites in the iron involved in the active center of cytochrome P450 are coupled by nitrogen atoms from the porphyrin molecule. The fifth... 

These ort/io-glucosylated porphyrin metal complexes have been shown to be active catalysts for aUcene epoxidation with certain asymmetric induction due to the presence of chiral sugar substituents in the vicinity of the metal center. However, as far as their medicinal apphcations are concerned, it was demonstrated that their deprotected, neutral derivatives exhibit neither toxicity nor phototoxicity against tumoral cells 1117]. A possible explanation for that considers a certain degree of globular structure for the molecules, which prevents suitable cell penetration. 

Thin films of porphyrin-metal polyamides have been prepared by the interfacial polymerization of tetrakis chloride derivatives with either aliphatic dianines or with tetrakis amino derivatives of the porphyrin-metal complexes. Films with thicknesses in the 0.0I-10 im range, display unique chemical asymmetry. Opposite surfaces show different concentrations of functional groups. When placed between identical semitransparent electrodes and irradiated with broad-band or pulsed laser light the films developed directional photopotential. Photopotentials of 25mV were seen. The directionality of the photopotentials is the result of electron transfer toward the acid surface of the asymmetric film. 

C.M. Xue, O. Birel, Y.N.A. Li, X Ma, M. Gao, A. Urbas, Q. Li, Porphyrin metal complex monolayer-protected gold nanorods a parallel facile synthesis and self-assembly. J. Colloid Interface Sci. 398, 1-6 (2013)... 

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