Manganese porphyrins oxidation with

Nevertheless, there are now some oxidation systems that do show catalytic turnover. For example, Breslow has reported a manganese porphyrin equipped with four hydrophobic binding sites in the form of cyclodextrins this mimic of cytochromep450 selectively oxidises unactivated carbon centres that are placed near the metal centre by virtue of the binding geometry (Fig. 3). Catalytic turnover is observed, but oxidative self-destruction of the catalyst competes with the desired chemistry use of a more robust, halogenated, porphyrin has recently solve this problem. ... 

Dramatic shape selectivities in competitive olefin epoxidation was observed with picnic basket metalloporphyrins312 313 designed to exclude bulky axial ligands on one sterically protected porphyrin face. When oxidized with PhIO in acetonitrile in the presence of the rigid p-xylyl-strapped porphyrin, cis-2-octene reacted selectively versus ds-cyclooctene or 2-methyl-2-pentene, giving >1000 reactivity ratios.313,314 Some immobilized manganese(III) porphyrins proved to be as efficient as their homogeneous equivalents in epoxidation with PhIO.151,315... 

A significant result was obtained in the study of manganese porphyrin behavior in aqueous solutions [70], Manganese porphyrins (Mn3+P) in aqueous alkaline solutions are easily oxidized to corresponded Mn4+P, which, in their turn, are able to catalyze H202 synthesis in accordance with the following reaction ... 

The results from the publications mentioned are of interest because they can help in the creation of effective catalytic systems containing porphyrins, which combine functions typical of multienzyme systems. The task in hand is the possible synthesis of bifunctional catalysts based on metalloporphyrin systems, when with the help of manganese porphyrins, for example, or SOD mimic, hydrogen peroxide is accumulated in the system. Afterwards, the accumulated hydrogen peroxide is used in oxidation reactions of various substrates with iron porphyrin components of the catalyst. 

Naruta Y, Sasayama M, Sasaki T. Oxygen evolution by oxidation of water with manganese porphyrin dimers. Angew Chem Int Ed. 1994 33(18) 1839—841. 

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