Síntese, caracterização e aplicação de catalisadores metaloporfirínicos suportados em MCM - 41




Metalloporphyrin catalysts are well known for their ability to carry out selective oxidation of organic substracts with many oxidizing agents. The current trend in the research is ancor active metalloporphyrins species on solid support, in order to achieve a better recover and reuse of these materials. Besides to prevent the formation of inactive dimmers and selfoxidation of metalloporphyrins, the imobilization can enhance the catalytic performance, regioselectivity, chemoselectivity and the stereoselectivity of the catalysed reactions. MCM 41 (Mobil composition of Mater) is a molecular mesoporous sieve that come up as a new support possibility for heterogen catalysis, with uniform pore size, high superficial area and high capacity of adsorption. Recently the immobilization of metalloporphyrin complexes in the large channels of MCM 41 has been studied on the alkene oxidation reactions. The work reported here presents the results of synthesis, characterization and application of three supported metalloporphyrin catalysts (FeTPPCl, MnTPPCl and CoTPP) anchored on MCM 41, in the reaction of cycloexene oxidation with hydrogen peroxide (H2O2). The association of procedures and techniques used in the present work was taken from studies involving synthetic models of biomimetic systems. The catalysts were successfully prepared by incorporation of the complexes within mesoporous molecular sieve MCM 41. FeTPPCl/MCM 41 showed high activity compared to CoTPP/MCM 41. However, the MnTPPCl /MCM 41 even in low concentration on the support, showed a considerable activity for a direct oxidation of cycloexene using hydrogen peroxide (H2O2) as oxidant agent.


catalisadores metaloporfirinas mcm-41 química orgânica quimica

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