The effect of peripheral substituents in metalloporphyrins on their catalytic activity in Lyons system

Synthesis of Metallo-Deuteroporphyrin Derivatives and the Study of Their Biomimetic Catalytic Properties

“…This phenomenon may be attributed to the fact that the redox potential of Co 2+ /Co 3+ is higher than that of other metals, because the catalytic activity of the metallo-pophyrin is influenced by the stability of different valent metal atoms and by the height of electric potential. In agreement with earlier observations (Haber et al, 2003), the catalytic activity of metallo-porphyrins increases as the redox potential goes up. For the cyclohexane oxidation catalyzed by simple Co(II)(DPDME) under the optimum conditions the conversion of cyclohexane, the yield of cyclohexanol and cyclohexanone and the turnover number of the catalyst reach 18.6%, 84.6% and 85147, respectively.…”

Porphyrins as Catalysts in Scalable Organic Reactions

“…Nonetheless, meso-phenyl-substituted metalloporphyrins bearing electronegative and bulky groups were classified as second-generation porphyrins such as meso-tetrakis(pentafluorophenyl) porphyrin iron(III) chloride and meso-tetramesitylporphyrin iron(III) chloride (TMPFeCl) (Figure 4b). The introduction of electron-withdrawing groups (such as halogens) in the β-pyrrole positions of second-generation porphyrins yields the so-called third generation porphyrin derivatives (Figure 4c) [22], which provide better catalytic activity over the other porphyrin generations, according to Haber and co-workers [23].…”

Catalytic activity in oxidation reactions of anionic iron(III) porphyrins immobilized on raw and grafted chrysotile

“…[1][2][3][4] This class of compounds is used in solution or following immobilization in organic amorphous polymers and crystalline inorganic materials such as silica, [5][6][7] zeolites, 8,9 clay from the smectite group (montmorillonite) 10,11 and others. [12][13][14][15][16] The use of metalloporphyrins substituted with electron-withdrawing groups (the so-called second generation porphyrins 17 ) and their immobilization, has resulted in efficient and selective catalysts for oxidation reactions, since the support can impose shape selectivity and promote a special environment, favoring the approach of the substrate to the active catalytic specie.…”

“…In this paper, we report the immobilization of the anionic iron III porphyrins {Na 4 [Fe(TDFSPP)]}Cl and {Na 4 [Fe (TCFSPP)]}Cl ( Figure 1) in raw and silanized chrysotile and its use as catalysts for oxidation reactions. Although chrysotile has a neutral structure and belongs to the same category as the clay minerals, no report has been found so far of its use as support for the immobilization of molecules with catalytic activity.…”