Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation
A new diMn III complex, Na[Mn 2(3-Me-5-SO 3-salpentO)(μ-MeO)(μ-AcO)(H 2O)]•4H 2O (1), where salpentOH = 1,5-bis(salicylidenamino) pentan-3-ol, was synthesized and structurally characterized. The complex possesses a bis(μ-alkoxo)(μ-acetato) triply bridged diMn III core, the structure of which is reta...
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paper:paper_00201669_v50_n18_p8973_Palopoli2023-06-08T14:40:40Z Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation catalase coordination compound hydrogen peroxide ligand manganese Schiff base article catalysis chemical structure chemistry metabolism spectroscopy Catalase Catalysis Coordination Complexes Hydrogen Peroxide Ligands Manganese Models, Molecular Schiff Bases Spectrum Analysis A new diMn III complex, Na[Mn 2(3-Me-5-SO 3-salpentO)(μ-MeO)(μ-AcO)(H 2O)]•4H 2O (1), where salpentOH = 1,5-bis(salicylidenamino) pentan-3-ol, was synthesized and structurally characterized. The complex possesses a bis(μ-alkoxo)(μ-acetato) triply bridged diMn III core, the structure of which is retained upon dissolution. Complex 1 is highly efficient to disproportionate H 2O 2 in an aqueous solution of pH ≥ 8.5 or in DMF, with only a slight decrease of activity. Electrospray ionization mass spectrometry, EPR, and UV-vis spectroscopy used to monitor the H 2O 2 disproportionation in buffered basic medium, suggest that the major active form of the catalyst during cycling occurs in the Mn III 2 oxidation state and that the starting complex retains the dinuclearity and composition during catalysis, with the acetate that moves from bridging to terminal ligand. UV-vis and Raman spectroscopy of H 2O 2 + 1 + Bu 4NOH mixtures in DMF suggest that the catalytic cycle involves Mn III 2/Mn IV 2 oxidation levels. At pH 10.6 in an Et 3N/Et 3NH + buffer, complex 1 catalyzes dismutation of H 2O 2 with saturation kinetics on the substrate, first order dependence on the catalyst, and k cat/K M = 16(1) ×10 2 s -1 M -1. During catalysis, the exogenous base contributes to retain the integrity of the bis(μ-alkoxo) doubly bridged diMn core and favors the formation of the catalyst-peroxide adduct (low value of K M), rendering 1 a highly efficient catalyst for H 2O 2 disproportionation. © 2011 American Chemical Society. 2011 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00201669_v50_n18_p8973_Palopoli http://hdl.handle.net/20.500.12110/paper_00201669_v50_n18_p8973_Palopoli |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
catalase coordination compound hydrogen peroxide ligand manganese Schiff base article catalysis chemical structure chemistry metabolism spectroscopy Catalase Catalysis Coordination Complexes Hydrogen Peroxide Ligands Manganese Models, Molecular Schiff Bases Spectrum Analysis |
| spellingShingle |
catalase coordination compound hydrogen peroxide ligand manganese Schiff base article catalysis chemical structure chemistry metabolism spectroscopy Catalase Catalysis Coordination Complexes Hydrogen Peroxide Ligands Manganese Models, Molecular Schiff Bases Spectrum Analysis Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation |
| topic_facet |
catalase coordination compound hydrogen peroxide ligand manganese Schiff base article catalysis chemical structure chemistry metabolism spectroscopy Catalase Catalysis Coordination Complexes Hydrogen Peroxide Ligands Manganese Models, Molecular Schiff Bases Spectrum Analysis |
| description |
A new diMn III complex, Na[Mn 2(3-Me-5-SO 3-salpentO)(μ-MeO)(μ-AcO)(H 2O)]•4H 2O (1), where salpentOH = 1,5-bis(salicylidenamino) pentan-3-ol, was synthesized and structurally characterized. The complex possesses a bis(μ-alkoxo)(μ-acetato) triply bridged diMn III core, the structure of which is retained upon dissolution. Complex 1 is highly efficient to disproportionate H 2O 2 in an aqueous solution of pH ≥ 8.5 or in DMF, with only a slight decrease of activity. Electrospray ionization mass spectrometry, EPR, and UV-vis spectroscopy used to monitor the H 2O 2 disproportionation in buffered basic medium, suggest that the major active form of the catalyst during cycling occurs in the Mn III 2 oxidation state and that the starting complex retains the dinuclearity and composition during catalysis, with the acetate that moves from bridging to terminal ligand. UV-vis and Raman spectroscopy of H 2O 2 + 1 + Bu 4NOH mixtures in DMF suggest that the catalytic cycle involves Mn III 2/Mn IV 2 oxidation levels. At pH 10.6 in an Et 3N/Et 3NH + buffer, complex 1 catalyzes dismutation of H 2O 2 with saturation kinetics on the substrate, first order dependence on the catalyst, and k cat/K M = 16(1) ×10 2 s -1 M -1. During catalysis, the exogenous base contributes to retain the integrity of the bis(μ-alkoxo) doubly bridged diMn core and favors the formation of the catalyst-peroxide adduct (low value of K M), rendering 1 a highly efficient catalyst for H 2O 2 disproportionation. © 2011 American Chemical Society. |
| title |
Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation |
| title_short |
Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation |
| title_full |
Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation |
| title_fullStr |
Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation |
| title_full_unstemmed |
Synthesis, characterization, and catalase activity of a water-soluble diMn III complex of a sulphonato-substituted schiff base ligand: An efficient catalyst for H 2O 2 disproportionation |
| title_sort |
synthesis, characterization, and catalase activity of a water-soluble dimn iii complex of a sulphonato-substituted schiff base ligand: an efficient catalyst for h 2o 2 disproportionation |
| publishDate |
2011 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00201669_v50_n18_p8973_Palopoli http://hdl.handle.net/20.500.12110/paper_00201669_v50_n18_p8973_Palopoli |
| _version_ |
1768543355391705088 |