Metalloporphyrins, supported

Scheme II. Schematic representation of sulfonated metalloporphyrins supported on different polyvinylpyridine polymers and Amberlite-IRA-900.

Figure 18. Sulphonated metalloporphyrins supported on poly(vinylpyridinium)polymers [325].

Oxygenation Reactions Catalyzed by Supported Sulfonated Metalloporphyrins... 

A new trend in the field of oxidations catalyzed by metalloporphyrin complexes is the use of these biomimetic catalysts on various supports ion-exchange resins, silica, alumina, zeolites or clays. Efficient supported metalloporphyrin catalysts have been developed for the oxidation of peroxidase-substrates, the epoxidation of olefins or the hydroxylation of alkanes. 

Cyclooctene epoxidation catalyzed by supported sulfonated metalloporphyrins. 

In conclusion, the concept of the proximal effect is a key factor in metalloporphyrin-catalyzed reactions, not only for soluble complexes, but also for supported catalysts. 

First of all, I would like to express my gratitude to the institutions that facilitated this work. Studies related to the formation, properties, and reactivity of metalloporphyrins were supported by grants from the Alexander von Humboldt Stiftung (fellowship 2005-2006), by the Deutsche Forschungsgemeinschaft through SFB 583, Redox-Active Metal Complexes Control of Reactivity via Molecular Architectures and by a grant of computer time on the Hochstleistungsrechner in Bayern II (HLRB II). 

Polar chlorophyll derivatives and metalloporphyrin derivatives such as Cu2+ and Zn2+ pheophytins can also be analyzed by C18 reversed-phase HPLC. Appropriate standards must be used see UNITF4.2 for polar chlorophyll derivatives, or see Support Protocol 2 for Cu2+ and Zn2+ pheophytin standards. Gradient solvent conditions and flow rates are given in Tables F4.4.3 and F4.4.4. Otherwise, the separation is performed as described for chlorophylls and nonpolar derivatives (see Basic Protocol). Using this method, separation of polar chlorophyll derivatives can be achieved in 20 to 25 min, and separation of the metalloporphyrin derivatives in 20 to 25 min. Examples of chromatograms obtained for polar derivatives, Zn2+ pheophytins, and Cu2+ pheophytins are shown in Figures F4.4.2, F4.4.3, and F4.4.4, respectively. 

Luminescence and Photoelectrochemistry of Surfactant Metalloporphyrin Assemblies on Solid Supports... 

The complex [Rh(TPP)(C02Et)] (reaction 42) is diamagnetic and monomeric in dichloromethane.195 The presence of an ethoxycarbonyl ligand was supported by the strong carbonyl stretch at 1700 cm-1, and the regeneration of [Rh(TPP)Cl(CO)] and ethanol via treatment with HC1. Related metalloporphyrins of the type [RhL-(Me2NH)2] (L = TPP or etioporphyrin) have been synthesized, and their structures... 

The data seem to support an alternative mechanism compared with the so-called Lyons mechanism in which O2 is activated forming a metal-oxo (M=0) species.1831 Via reaction of a second metalloporphyrin with a primarily formed superoxo (Me-OO0) or peroxo species, a metal-oxo is formed, reacting eventually with an alkane according to the oxygen rebound mechanism. Alternatively, radicals present in solution, upon reaction with dioxygen, may form alkyl hydroperoxides that are decomposed by metalloporphyrins.[83]... 

No reports have appeared on oxidation of substrates using metalloporphyrins under conditions at which dioxygen complexes are known to exist at ambient temperatures, for example, the 02 adducts of specially designed picket fence (5, 29, 132) and polymer-supported metalloporphyrins (133), (py)Cr(7TP)02 (134), and... 

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