Manganese porphyrin derivatives

Fig. 2.20 (a) Complex plane plots of ER signals for monolayers of three different manganese porphyrin derivatives on Au electrodes in DMSO. The measurements were all conducted at their formal potentials at a wavelength of 460 nm with A ac=50 mV(rms). The lengths of alkyl chain... 

Fig. 37 Catalytic cycle for the fluorination of aliphatic substrates initiated by the manganese porphyrin derivative 107...

Recently, the high inhibitory efficiency of metalloporphyrins has been shown in lipid peroxidation of rat brain homogenates [346]. It was found that manganese and cobalt porphyrins were very effective inhibitors of lipid peroxidation while iron and especially zinc porphyrins had very weak inhibitory activity, if any. For example, /50 values were equal to 21, 29, 212, 946 pmol 1 1 for CoTBAP, MnTBAP, FeTBAP, and ZnTBAP, respectively, where TBAP is 5,10,15,20-tetrakis [4-carboxyphenyl]porphyrin similar values were obtained for other porphyrin derivatives. 

Terphenyl ligands have also been utilized in the context of metalloporph-yrin chemistry. For example, the use of four Triph substituents at the periphery of manganese and iron porphyrin derivatives dramatically in-... 

It has been observed that PI14PHSO5 alone does not transfer its oxygen to manganese porphyrin. It is necessary to add either imidazole or pyridine derivatives, i.e. species which act as axial ligands in metalloporphyrins and are known to accelerate also the catalytic oxidation of organic substances . The kinetics and mechanism of manganese porphyrins oxidation by PI14PHSO5 were well studied . ... 

Amination of alkanes (cyclohexane, heptane, adamantane) was achieved with iron and manganese porphyrin catalysts by tosylimidoiodobenzene to yield tosyl-amino derivatives.200 Selective 1-substitution of adamantane (56% yield) and 2-substitution of heptane (66% selectivity) were reported. 

It is shown [100] that polyhalide derivatives of iron and manganese porphyrin catalysts applied on Si02 and polymeric matrices via their amino functional group were successfully synthesized. 

Irradiation of manganese azides derived from Mn(III) porphyrin, cyclam, and polyamide complexes represents one of the earliest methods reported for the preparation of nitrido manganese complexes (Eq. (40)) [50], Additional methods have become available for the synthesis of manganese nitrides that utilize ammonia in combination with oxidants such as Cl2, PhIO, NaCIO, and NBS (Eq. (41)) [51-53]. Employing these methods, the manganese nitrides incorporating porphyrin, phath-locyanine, cyclam, salen, and bidentate Schiff base complexes have been documen-... 

The transfer of a nitrogen atom from a metal nitride to another metal complex is a process that works quite well with Mnv nitrides. Thus manganese nitrides derived from porphyrin or salen ligands participate in nitride transfer reaction to salen and porphyrin Mnm complexes to give new nitrido manganese products (Eq. (42) Chart 2) [55,56]. 

Much of the early interest in manganese porphyrins had its origins in prior work, - involving manganese phthalocyanine (193 [MnPc]. Phthalocyanines (including those of manganese) were reviewed by Lever in 1962. Since then, the general metal-ion chemistry of Pc and its derivatives has been discussed in numerous books and articles two more recent reviews are by Boucher and Berezin. ... 

Beside the Mn([15]aneN5) derivatives and manganese porphyrins, the Mn(III)(salen) complexes have excellent potential... 

IV-Tosyliminoiodanes, ArINTs, have found synthetic application as useful nitrene precursors in transition metal catalyzed amidation of saturated C—H bonds in various organic substrates. Breslow and coworkers have developed the regioselective amidation of steroidal derivatives catalyzed by metalloporphyrins [690,691]. Specifically, the aromatic steroid equilenin acetate 657 undergoes regioselective and stereoselective amidation catalyzed by a manganese porphyrin using PhINTs as the nitrene donor (Scheme 3.261) [690],... 

Manganese porphyrins containing non-planar macrocycles such as DPP and Vx DPP (x = 4, 8, 20 or 28), T(2,6-(OMe)2, 3, 5-Cl2)PP have been synthesized [169] and investigated electrochemically [170, 171], as have Mn(III) complexes with a positively charged macrocycle [53] such as in the case of [(TMpyP)MnCl] . The DPP derivatives show electrochemical behavior similar to manganese porphyrins with planar macrocycles (such as TPP), but the stability of the reduced and oxidized forms of the porphyrins as well as the potentials at which they are electrogenerated will vary with the type, number, and position of the added substituents. 

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