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Synthesis, single crystal X-ray, spectroscopic characterization and biological activities of Mn2+, Co2+, Ni2+ and Fe3+ complexes. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2019.127240] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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2
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Shova S, Vlad A, Cazacu M, Krzystek J, Ozarowski A, Malček M, Bucinsky L, Rapta P, Cano J, Telser J, Arion VB. Dinuclear manganese(iii) complexes with bioinspired coordination and variable linkers showing weak exchange effects: a synthetic, structural, spectroscopic and computation study. Dalton Trans 2019; 48:5909-5922. [DOI: 10.1039/c8dt04596h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High-resolution HFEPR indicates weak exchange interactions between MnIII ions in agreement with DFT calculations.
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Affiliation(s)
- Sergiu Shova
- Inorganic Polymers Department
- “Petru Poni” Institute of Macromolecular Chemistry
- Iasi 700487
- Romania
| | - Angelica Vlad
- Inorganic Polymers Department
- “Petru Poni” Institute of Macromolecular Chemistry
- Iasi 700487
- Romania
| | - Maria Cazacu
- Inorganic Polymers Department
- “Petru Poni” Institute of Macromolecular Chemistry
- Iasi 700487
- Romania
| | - J. Krzystek
- National High Magnetic Field Laboratory
- Florida State University
- Tallahassee
- USA
| | - Andrew Ozarowski
- National High Magnetic Field Laboratory
- Florida State University
- Tallahassee
- USA
| | - Michal Malček
- Institute of Physical Chemistry and Chemical Physics
- Slovak University of Technology in Bratislava
- 81237 Bratislava
- Slovak Republic
| | - Lukas Bucinsky
- Institute of Physical Chemistry and Chemical Physics
- Slovak University of Technology in Bratislava
- 81237 Bratislava
- Slovak Republic
| | - Peter Rapta
- Institute of Physical Chemistry and Chemical Physics
- Slovak University of Technology in Bratislava
- 81237 Bratislava
- Slovak Republic
| | - Joan Cano
- Institut de Ciència Molecular
- Universitat de València
- 46980 Paterna
- Spain
| | - Joshua Telser
- Department of Biological
- Physical and Health Sciences
- Roosevelt University
- Chicago
- USA
| | - Vladimir B. Arion
- Institute of Inorganic Chemistry of the University of Vienna
- A1090 Vienna
- Austria
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3
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Magherusan AM, Nelis DN, Twamley B, McDonald AR. Catechol oxidase activity of comparable dimanganese and dicopper complexes. Dalton Trans 2018; 47:15555-15564. [PMID: 30345446 DOI: 10.1039/c8dt01378k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Synthetic Cu complexes have been widely investigated as model systems for catechol oxidase enzymes. The catechol oxidase reactivity of Mn complexes has been less explored, and the effect of metal substitution in catecholase mimics has not been explored. A series of Mn and Cu complexes supported by the same poly-benzimidazole ligand framework have been synthesised and investigated in catecholase activity in acetonitrile medium using 3,5-di-tert-butylcatechol (3,5-DTBC) as a substrate. The Cu complexes proved to be good catechol oxidase mimics with moderate kcat values (∼45 h-1). The kinetic parameters for Mn complexes exhibited lower kcat values (∼8-40 h-1) when compared to the Cu complexes. Our findings demonstrate that later transition metals supported by relatively electron rich ligands yield the highest kcat values for catechol oxidation.
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Affiliation(s)
- Adriana M Magherusan
- School of Chemistry, Trinity College Dublin, The University of Dublin, College Green, Dublin 2, Ireland.
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4
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Joshi T, Kubeil M, Nsubuga A, Singh G, Gasser G, Stephan H. Harnessing the Coordination Chemistry of 1,4,7-Triazacyclononane for Biomimicry and Radiopharmaceutical Applications. Chempluschem 2018; 83:554-564. [DOI: 10.1002/cplu.201800103] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Tanmaya Joshi
- Institute of Radiopharmaceutical Cancer Research; Helmholtz-Zentrum Dresden-Rossendorf; Bautzner Landstrasse 400 01328 Dresden Germany
| | - Manja Kubeil
- Institute of Radiopharmaceutical Cancer Research; Helmholtz-Zentrum Dresden-Rossendorf; Bautzner Landstrasse 400 01328 Dresden Germany
| | - Anne Nsubuga
- Institute of Radiopharmaceutical Cancer Research; Helmholtz-Zentrum Dresden-Rossendorf; Bautzner Landstrasse 400 01328 Dresden Germany
| | - Garima Singh
- Institute of Radiopharmaceutical Cancer Research; Helmholtz-Zentrum Dresden-Rossendorf; Bautzner Landstrasse 400 01328 Dresden Germany
| | - Gilles Gasser
- Chimie ParisTech; PSL University; Laboratory for Inorganic Chemical Biology; 75005 Paris France
| | - Holger Stephan
- Institute of Radiopharmaceutical Cancer Research; Helmholtz-Zentrum Dresden-Rossendorf; Bautzner Landstrasse 400 01328 Dresden Germany
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5
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Yang Y, Zhong W, Nie B, Chen J, Wei Z, Liu X. Synergetic oxidation of ethylbenzene to acetophenone catalyzed by manganese(II) complexes bearing pendant iodophenyl groups. J Organomet Chem 2017. [DOI: 10.1016/j.jorganchem.2017.10.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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6
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Su E, Guven A, Kani I. Oxygen bridged Homobinuclear Mn(II) compounds with Anthranilic acid: Theoretical calculations, oxidation and catalase activity. Appl Organomet Chem 2017. [DOI: 10.1002/aoc.4105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Esra Su
- Department of ChemistryFaculty of Science & Letters, Istanbul Technical University Maslak, 34469 Istanbul Turkey
- Department of Chemistry, Faculty of ScienceAnadolu University 26470 Eskisehir Turkey
| | - Alaettin Guven
- Department of Chemistry, Faculty of ScienceAnadolu University 26470 Eskisehir Turkey
| | - Ibrahim Kani
- Department of Chemistry, Faculty of ScienceAnadolu University 26470 Eskisehir Turkey
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7
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Supramolecular interactions through lone pair(lp)–π and hydrogen bonding in cobalt(III) and manganese(II) derivatives of N,N′-dimethylvioluric acid: A combined experimental and theoretical study. Inorganica Chim Acta 2015. [DOI: 10.1016/j.ica.2015.06.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Abdolahzadeh S, Boyle NM, Hoogendijk ML, Hage R, de Boer JW, Browne WR. The role of carboxylato ligand dissociation in the oxidation of chrysin with H₂O₂ catalysed by [Mn₂(III,IV)(μ-CH₃COO)(μ-O)₂(Me₄dtne)](PF₆)₂. Dalton Trans 2014; 43:6322-32. [PMID: 24647519 DOI: 10.1039/c3dt53174k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The aqueous and non-aqueous chemistry of the complex [Mn2(III,IV)(μ-CH3COO)(μ-O)2(Me4dtne)](PF6)2 (where Me4dtne = 1,2-bis(4,7-dimethyl-1,4,7-triazacyclonon-1-yl)ethane), which has been demonstrated as an exceptionally active catalyst in the bleaching of raw cotton and especially wood pulp at high pH (>11), is explored by UV/vis absorption, Raman and EPR spectroscopies and cyclic voltammetry. The data indicate that dissociation of the μ-acetato bridge is essential to the catalyst activity and rationalises the effect of sequestrants such as DTPA on its performance.
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Affiliation(s)
- Shaghayegh Abdolahzadeh
- Stratingh Institute for Chemistry, Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
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9
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exo-Diastereoisomer of 10-aryl-1,4,7-triazabicyclo[5.2.1]decane as intermediary in specific derivatisation of triazacyclononane. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.04.057] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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10
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Bräuer B, Schaarschmidt D, Flohrer C, Rüffer T, Tripke S, Hildebrandt A, Walfort B, Sorace L, Lang H. A dimanganese(II) complex with bridging chlorides: Synthesis, electrochemistry, magnetic behavior, structure and bonding. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2010.09.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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A New Dinuclear Copper (II) Complex of a Bis-macrocyclic Ligand: Synthesis, Characterization, Crystal Structure and Magnetic Properties. CHINESE J CHEM 2010. [DOI: 10.1002/cjoc.20010190812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Timmons JC, Hubin TJ. Preparations and applications of synthetic linked azamacrocycle ligands and complexes. Coord Chem Rev 2010. [DOI: 10.1016/j.ccr.2009.09.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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13
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Singla M, Mathur P. Oxidation of alcohols using a manganese (II) complex based on a pentakis benzimidazole amide ligand. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 74:536-543. [PMID: 19660981 DOI: 10.1016/j.saa.2009.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 05/13/2009] [Accepted: 07/01/2009] [Indexed: 05/28/2023]
Abstract
A pentakis benzimidazole based penta-amide ligand diethylenetriamine-N,N,N',N',N''-pentakis(2-methyl benzimidazolyl)penta-amide [GBDTPA] has been synthesized and utilized to prepare Mn (II) complexes of general composition [Mn(2)(GBDTPA)X(4)], where X is an exogenous anionic ligand (X = Cl(-), NO(3)(-) and Br(-)). The oxidation of alcohols has been investigated using [Mn(2)(GBDTPA)Cl(4)] as the catalyst and TBHP as an alternate source of oxygen. The respective aldehydic products have been isolated and characterized by (1)H NMR.
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Affiliation(s)
- Manisha Singla
- Department of Chemistry, Delhi University, Delhi 110007, India.
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14
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Groni S, Hureau C, Guillot R, Blondin G, Blain G, Anxolabéhère-Mallart E. Characterizations of chloro and aqua Mn(II) mononuclear complexes with amino-pyridine ligands. Comparison of their electrochemical properties with those of Fe(II) counterparts. Inorg Chem 2009; 47:11783-97. [PMID: 19007154 DOI: 10.1021/ic8015172] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The solution behavior of mononuclear Mn(II) complexes, namely, [(L(5)(2))MnCl](+) (1), [(L(5)(3))MnCl](+) (2), [(L(5)(2))Mn(OH(2))](2+) (3), [(L(5)(3))Mn(OH(2))](2+) (4), and [(L(6)(2))Mn(OH(2))](2+) (6), with L(5)(2/3) and L(6)(2) being penta- and hexadentate amino-pyridine ligands, is investigated in MeCN using EPR, UV-vis spectroscopies, and electrochemistry. The addition of one chloride ion onto species 6 leads to the formation of the complex [(L(6)(2))MnCl](+) (5) that is X-ray characterized. EPR and UV-vis spectra indicate that structure and redox states of complexes 1-6 are maintained in MeCN solution. Chloro complexes 1, 2, and 5 show reversible Mn(II)/Mn(III) process at 0.95, 1.02, and 1.05 V vs SCE, respectively, whereas solvated complexes 3, 4, and 6 show an irreversible anodic peak around 1.5 V vs SCE. Electrochemical oxidations of 1 and 5 leading to the Mn(III) complexes [(L(5)(2))MnCl](2+) (7) and [(L(6)(2))MnCl](2+) (8) are successful. The UV-vis signatures of 7 and 8 show features associated with chloro to Mn(III) LMCT and d-d transitions. The X-ray characterization of the heptacoordinated Mn(III) species 8 is also reported. The analogous electrochemical generation of the corresponding Mn(III) complex was not possible when starting from 2. The new mixed-valence di-mu-oxo [(L(5)(2))Mn(muO)(2)Mn(L(5)(2))](3+) species (9) can be obtained from 3, whereas the sister [(L(5)(3))Mn(muO)(2)Mn(L(5)(3))](3+) species can not be generated from 4. Such different responses upon oxidations are commented on with the help of comparison with related Mn/Fe complexes and are discussed in relation with the size of the metallacycle formed between the diamino bridge and the metal center (5- vs 6-membered). Lastly, a comparison between redox potentials of the studied Mn(II) complexes with those of Fe(II) analogues is drawn and completed with previously reported data on Mn/Fe isostructural systems. This gives us the opportunity to get some indirect insights into the metal specificity encountered in enzymes among which superoxide dismutase is the archetypal model.
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Affiliation(s)
- Sihem Groni
- Equipe de Chimie Inorganique, Institut de Chimie Moléculaire et des Matériaux d'Orsay, Université Paris-Sud 11, UMR 8182 CNRS, Orsay F-91405, France
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15
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Hureau C, Groni S, Guillot R, Blondin G, Duboc C, Anxolabéhère-Mallart E. Syntheses, X-ray structures, solid state high-field electron paramagnetic resonance, and density-functional theory investigations on chloro and aqua Mn(II) mononuclear complexes with amino-pyridine pentadentate ligands. Inorg Chem 2008; 47:9238-47. [PMID: 18817370 DOI: 10.1021/ic800551u] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The two pentadentate amino-pyridine ligands L5(2) and L5(3) (L5(2) and L5(3) stand for the N-methyl-N,N',N'-tris(2-pyridylmethyl)ethane-1,2-diamine and the N-methyl-N,N',N'-tris(2-pyridylmethyl)propane-1,3-diamine, respectively) were used to synthesize four mononuclear Mn(II) complexes, namely [(L5(2))MnCl](PF6) (1(PF6)), [(L5(3))MnCl](PF6) (2(PF6)), [(L5(2))Mn(OH2)](BPh4)2 (3(BPh4)2), and [(L5(3))Mn(OH2)](BPh4)2 (4(BPh4)2). The X-ray diffraction studies revealed different configurations for the ligand L5(n) (n = 2, 3) depending on the sixth exogenous ligand and/or the counterion. Solid state high-field electron paramagnetic resonance spectra were recorded on complexes 1-4 as on previously described mononuclear Mn(II) systems with tetra- or hexadentate amino-pyridine ligands. Positive and negative axial zero-field splitting (ZFS) parameters D were determined whose absolute values ranged from 0.090 to 0.180 cm(-1). Density-functional theory calculations were performed unraveling that, in contrast with chloro systems, the spin-spin and spin-orbit coupling contributions to the D-parameter are comparable for mixed N,O-coordination sphere complexes.
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Affiliation(s)
- Christelle Hureau
- Equipe de Chimie Inorganique, Institut de Chimie Moleculaire et des Materiaux d'Orsay, UMR 8182 CNRS, Universite Paris-Sud, 91405 Orsay Cedex, France
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16
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Groni S, Dorlet P, Blain G, Bourcier S, Guillot R, Anxolabéhère-Mallart E. Reactivity of an Aminopyridine [LMnII]2+ Complex with H2O2. Detection of Intermediates at Low Temperature. Inorg Chem 2008; 47:3166-72. [DOI: 10.1021/ic702238z] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Sihem Groni
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Equipe de Chimie Inorganique, Université Paris XI, 91405 Orsay, France, Laboratoire du Stress Oxydant et Détoxication, URA CNRS 2096-IBITECS CEA Saclay, Bat. 532, 91191 Gif-sur-Yvette Cedex, France, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Université Paris XI, 91405 Orsay, France, and Ecole Polytechnique 91128 Palaiseau, France
| | - Pierre Dorlet
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Equipe de Chimie Inorganique, Université Paris XI, 91405 Orsay, France, Laboratoire du Stress Oxydant et Détoxication, URA CNRS 2096-IBITECS CEA Saclay, Bat. 532, 91191 Gif-sur-Yvette Cedex, France, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Université Paris XI, 91405 Orsay, France, and Ecole Polytechnique 91128 Palaiseau, France
| | - Guillaume Blain
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Equipe de Chimie Inorganique, Université Paris XI, 91405 Orsay, France, Laboratoire du Stress Oxydant et Détoxication, URA CNRS 2096-IBITECS CEA Saclay, Bat. 532, 91191 Gif-sur-Yvette Cedex, France, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Université Paris XI, 91405 Orsay, France, and Ecole Polytechnique 91128 Palaiseau, France
| | - Sophie Bourcier
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Equipe de Chimie Inorganique, Université Paris XI, 91405 Orsay, France, Laboratoire du Stress Oxydant et Détoxication, URA CNRS 2096-IBITECS CEA Saclay, Bat. 532, 91191 Gif-sur-Yvette Cedex, France, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Université Paris XI, 91405 Orsay, France, and Ecole Polytechnique 91128 Palaiseau, France
| | - Régis Guillot
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Equipe de Chimie Inorganique, Université Paris XI, 91405 Orsay, France, Laboratoire du Stress Oxydant et Détoxication, URA CNRS 2096-IBITECS CEA Saclay, Bat. 532, 91191 Gif-sur-Yvette Cedex, France, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Université Paris XI, 91405 Orsay, France, and Ecole Polytechnique 91128 Palaiseau, France
| | - Elodie Anxolabéhère-Mallart
- Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Equipe de Chimie Inorganique, Université Paris XI, 91405 Orsay, France, Laboratoire du Stress Oxydant et Détoxication, URA CNRS 2096-IBITECS CEA Saclay, Bat. 532, 91191 Gif-sur-Yvette Cedex, France, Institut de Chimie Moléculaire et des Matériaux d’Orsay, UMR CNRS 8182, Université Paris XI, 91405 Orsay, France, and Ecole Polytechnique 91128 Palaiseau, France
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Yang YS, Gu W, Zhang LZ, Gao FX, Yan SP. A new terephthalato-bridged binuclear manganese(II) complex [Mn2(dmptacn)2( p -bdc)](ClO4)2: synthesis, structure and properties. J COORD CHEM 2007. [DOI: 10.1080/00958970701209880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Yong-Sheng Yang
- a Department of Chemistry , Nankai University , 300071, Tianjin, People's Republic of China
| | - Wen Gu
- a Department of Chemistry , Nankai University , 300071, Tianjin, People's Republic of China
| | - Li-Zhi Zhang
- a Department of Chemistry , Nankai University , 300071, Tianjin, People's Republic of China
| | - Fen-Xian Gao
- a Department of Chemistry , Nankai University , 300071, Tianjin, People's Republic of China
| | - Shi-Ping Yan
- a Department of Chemistry , Nankai University , 300071, Tianjin, People's Republic of China
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Balogh E, He Z, Hsieh W, Liu S, Tóth E. Dinuclear complexes formed with the triazacyclononane derivative ENOTA4-: high-pressure 17O NMR evidence of an associative water exchange on [MnII2(ENOTA)(H2O)2]. Inorg Chem 2007; 46:238-50. [PMID: 17198433 DOI: 10.1021/ic0616582] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mn2+ has five unpaired d-electrons, a long electronic relaxation time, and labile water exchange, all of which make it an attractive candidate for contrast agent application in medical magnetic resonance imaging. In the quest for stable and nonlabile Mn2+ complexes, we explored a novel dimeric triazacyclononane-based ligand bearing carboxylate functional groups, H4ENOTA. The protonation constants of the ligand and the stability constants of the complexes formed with some endogenously important metals (Ca2+, Cu2+, Zn2+), as well as with Mn2+ and Ce3+, have been assessed by NMR methods, potentiometry, and UV-vis spectrophotometry. Overall, the thermodynamic stability of the complexes is lower as compared to that of the corresponding NOTA analogues (H3NOTA, 1,4,7-triaazacyclononane-1,4,7-triacetic acid). The crystal structure of Mn2(ENOTA)(H2O) x 5H2O contains two six-coordinated Mn2+, in addition to the three amine nitrogens and the two oxygens from the pendent monodentate carboxylate groups, and one water (Mn2) or one bridging carboxylate oxygen (Mn1) completes the coordination sphere of the metal ion. In an aqueous solution, this bridging carboxylate is replaced by a water molecule, as evidenced by the 17O chemical shifts and proton relaxivity data that point to monohydration for both metal ions in the dinuclear complex. A variable-temperature and -pressure 17O NMR study has been performed on [Mn2(ENOTA)(H2O)2] to assess the rate and, for the first time on a Mn2+ chelate, also the mechanism of the water exchange. The inner sphere water is slightly more labile in [Mn2(ENOTA)(H2O)2] (k298ex = 5.5 x 107 s-1) than in the aqua ion (2.1 x 107 s-1, Merbach, A. E.; et al. Inorg. Chem. 1980, 19, 3696). The water exchange proceeds via an almost limiting associative mechanism, as evidenced by the large negative activation volume (deltaV = -10.7 cm3 mol-1). The proton relaxivities measured on [Mn2(ENOTA)(H2O)2] show a low-field dispersion at approximately 0.1 MHz arising from a contact interaction between the MnII electron spin and the water proton nuclear spins.
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Affiliation(s)
- Edina Balogh
- Laboratoire de chimie inorganique et bioinorganique, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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Groni S, Blain G, Guillot R, Policar C, Anxolabéhère-Mallart E. Reactivity of MnIIwith Superoxide. Evidence for a [MnIIIOO]+Unit by Low-Temperature Spectroscopies. Inorg Chem 2007; 46:1951-3. [PMID: 17311375 DOI: 10.1021/ic062063+] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Manganese superoxide dismutase cycles between the MnIII and MnII states to produce oxygen and hydrogen peroxide from superoxide. The formation of an adduct has been suggested, but its nature remains questionable because both [MnIIOO-] and [MnIIIOO2-] redox states have been proposed. Study of the reactivity of superoxide with manganese complexes is of current interest. The reaction of [(L)MnII]2+ [L = N-methyl-N,N',N'-tris(2-pyridylmethyl)ethane-1,2-diamine] with potassium superoxide has been investigated at low temperature in an anhydrous solvent using various techniques. Upon the addition of ca. 2 equiv of potassium superoxide, the [(L)MnII]2+ colorless solution turned blue and the UV-vis spectrum displayed a band at 590 nm (165 M(-1) cm(-1)) and a shoulder at 430 nm (100 M(-1) cm(-1)). Electrospray ionization mass spectrometry showed a peak (m/z = 434.1) assigned to [(L)MnO2]+. The X-band electron paramagnetic resonance spectrum parallel mode displayed a six-line signal separated by 6.6 mT and centered at 86 mT (g = 8.1). These results support the formation of an [MnIIIOO]+ adduct.
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Affiliation(s)
- Sihem Groni
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, UMR 8182, Université Paris XI, 91405 Orsay, France
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Shakir M, Begum N, Azim Y, Parveen S. Synthesis of 14‐Membered Pentaazabis(Macrocyclic) Complexes of Co(II), Ni(II), Cu(II), and Zn(II) Derived from Hydrazine and Their Physico‐chemical Studies. ACTA ACUST UNITED AC 2007. [DOI: 10.1081/sim-120024315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Mohammad Shakir
- a Division of Inorganic Chemistry, Department of Chemistry , Aligarh Muslim University , Aligarh, 202‐002, India
| | - Nishat Begum
- a Division of Inorganic Chemistry, Department of Chemistry , Aligarh Muslim University , Aligarh, 202‐002, India
| | - Yasser Azim
- a Division of Inorganic Chemistry, Department of Chemistry , Aligarh Muslim University , Aligarh, 202‐002, India
| | - Shama Parveen
- a Division of Inorganic Chemistry, Department of Chemistry , Aligarh Muslim University , Aligarh, 202‐002, India
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Gultneh Y, Tesema YT, Yisgedu TB, Butcher RJ, Wang G, Yee GT. Studies of a Dinuclear Manganese Complex with Phenoxo and Bis-acetato Bridging in the Mn2(II,II) and Mn2(II,III) States: Coordination Structural Shifts and Oxidation State Control in Bridged Dinuclear Complexes. Inorg Chem 2006; 45:3023-33. [PMID: 16562958 DOI: 10.1021/ic060039q] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The dinucleating ligand, 2,6-bis{[(2-(2-pyridyl)ethyl)(2-pyridylmethyl)-amino]-methyl}-4-methylphenol) (L1OH) reacts with Mn(ClO4)2.6H2O to form the dinuclear complex [Mn2(II,II)(L1O)(mu-OOCCH3)2]ClO4 (1). The electrolytic oxidation of 1 at 0.7 V (vs Ag/AgCl) produces the mixed valent complex [Mn2(II,III)(L1O)(mu-OOCCH3)2](ClO4)2 (1ox) quantitatively, while electrolysis at 0.20 V converts 1ox back to 1. X-ray crystallographic structures show that both 1 and 1ox are dinuclear complexes in which the two manganese ions are each in distorted octahedral coordination environments bridged by the phenoxo oxygen and two acetate ions. The structural changes that occur upon the oxidation 1 to 1ox suggest an extended pi-bonding system involving the phenoxo ring C-O(phenoxo)-Mn(II)-N(pyridyl) chain. In addition, as 1 is oxidized to 1ox, the rearrangements in the coordination sphere resulting from the oxidation of one Mn(II) ion to Mn(III) are transmitted via the bridging Mn-O(phenoxo) bonds and cause structural changes that render the site of the second manganese ion unfit for the +3 state and hence unstable to reduction. Thus the electrolytic oxidation of 1ox in acetonitrile at 1.20 V takes up slightly greater than 1 F of charge/mol of 1ox, but the starting complex, 1ox, is recovered, showing the instability of the Mn2(III,III) state that is formed with respect to reduction to 1ox. Variable-temperature magnetic susceptibility measurements of 1 and 1ox over the temperature range from 1.8 to 300 K can be modeled with magnetic coupling constants J = -4.3 and -4.1 cm(-1), respectively showing the weak antiferromagnetic coupling between the two manganese ions in each dinuclear complex, which is commonly observed among similar phenoxo- and bis-1,3-carboxylato-bridged dinuclear Mn2(II,II) and Mn2(II,III) complexes.
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Affiliation(s)
- Yilma Gultneh
- Department of Chemistry, Howard University, Washington, DC 20059, USA.
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Romba J, Kuppert D, Morgenstern B, Neis C, Steinhauser S, Weyhermüller T, Hegetschweiler K. The Coordination Chemistry of 1,4-Diazepan-6-amine. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200500690] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Graham B, Spiccia L, Batten SR, Skelton BW, White AH. Polynuclear nickel (II) and copper (II) complexes of hexaazamacrocycles incorporating pairs of diethylenetriamine subunits separated by aromatic spacers. Inorganica Chim Acta 2005. [DOI: 10.1016/j.ica.2005.06.052] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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24
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Li QX, Luo QH, Li YZ, Duan CY, Tu QY. A study on mono-, bis- and tris-N-functionalized 1,4,7-triazacyclononane with benzimidazolyl groups and their nickel(II) complexes. Inorganica Chim Acta 2005. [DOI: 10.1016/j.ica.2004.07.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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25
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Bonadio F, Senna MC, Ensling J, Sieber A, Neels A, Stoeckli-Evans H, Decurtins S. Cyano-Bridged Structures Based on [MnII(N3O2-Macrocycle)]2+: A Synthetic, Structural, and Magnetic Study. Inorg Chem 2005; 44:969-78. [PMID: 15859276 DOI: 10.1021/ic049209u] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Reactions between the complex [MnII(L)]2+, where L is a N3O2 macrocyclic ligand, and different cyanometalate precursors such as [M(CN)n]m- (M(III) = Cr, Fe; M(II) = Fe, Ni, Pd, Pt) lead to cyano-bridged molecular assemblies exhibiting a variety of structural topologies. The reaction between [MnII(L)]2+ and [FeII(CN)6]4- forms a trinuclear complex with formula [(MnII(L)(H2O))2(FeII(micro-CN)2(CN)4)] x 2MeOH x 10H2O (1) which crystallizes in the triclinic space group P1. The reaction between [MnII(L)]2+ and [M(II)(CN)4]2-, where M(II) = Ni (2), Pd (3), Pt (4), gives rise to three isostructural linear chain compounds with stoichiometry [(MnII(L))(M(II)(micro-CN)2(CN)2)]n and which crystallize in the monoclinic space group C2/c. The self-assembly between [MnII(L)]2+ with [M(III)(CN)6]3-, where M(III) = Cr (5), Fe (6, 7, 8), forms three types of compounds. Compounds 5 and 6 are isostructural (monoclinic, space group P2(1)/n), and the structures comprise anionic linear chains [(MnII(L))(M(III)(micro-CN)2(CN)4)]n(n-) with cationic trinuclear complexes [(MnII(L)(H2O))2(M(III)(micro-CN)2(CN)4)]+ as counterions. Using an excess of K3[FeIII(CN)6], an analogous compound to 6 but with K+ as counterion is obtained (7), which crystallizes in the triclinic space group P1. Compound 8 consists of 2-D layers with formula [(MnII(L))3(FeIII(micro-CN)4(CN)2)(FeIII(micro-CN)2(CN)4)]n x 2nMeOH; it crystallizes in the monoclinic space group P2(1)/n. The magnetic properties were investigated for all samples. In particular, compound 5, which shows antiferromagnetic exchange interactions between Mn(II) and Cr(III) ions through cyanide bridging ligands, has been studied in detail; the magnetic exchange parameter amounts to J = -7.5(7) cm(-1). Compound 8 shows a magnetically ordered phase below 6.4 K which is confirmed by Mössbauer spectroscopy; two hyperfine split spectra were observed below Tc from which IJI values of 2.1 and 1.6 cm(-1) could be deduced.
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Affiliation(s)
- Federica Bonadio
- Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
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Warden AC, Spiccia L, Hearn MTW, Boas JF, Pilbrow JR. The synthesis, structure and properties of copper(ii) complexes of asymmetrically functionalized derivatives of 1,4,7-triazacyclononane. Dalton Trans 2005:1804-13. [PMID: 15877151 DOI: 10.1039/b417739h] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction of 1-propylamino-4-acetato-1,4,7-triazacyclononane (L1), 1-benzyl-4-acetato-1,4,7-triazacyclononane (L2) and 1-benzyl-4-propylamino-1,4,7-triazacyclononane (L3) with a copper(II) salt gave Na2[CuL1](ClO4)3(1a), [CuL2]Cl (2) and [Cu2L32](ClO4)4.5H2O (3), respectively. [CuL4]ClO4 (4) was formed by reacting 1-formyl-4-ethylacetato-1,4,7-triazacyclononane with cupric chloride in aqueous solution. The X-ray crystal structures of the complexes reveal that the ligands generate distorted square pyramidal or square planar coordination environments about the Cu(II) centre, but in three complexes (1b, 3 and 4) weak interactions to an oxygen atom from a perchlorate anion and, in the case of 4, also to an amide nitrogen leading to tetragonally elongated octahedral Cu(II) geometries. In 4, the formyl group is found to reduce the coordinating ability of the macrocyclic nitrogen to which it is attached, as evidenced by the weak CuN interaction. The formation of five-membered chelate rings on coordination of the ligands further contributes to the distortion from the ideal geometries. The crystal lattices contain a number of novel supramolecular features. 1a contains a negatively charged sodium perchlorate chain of composition [Na2(ClO4)3]x(x-), with a complex series of Na-O-Na bridges flanked by [CuL1]+ units, while 3 contains highly complex hydrogen bonded sheets approximately 20 A thick that stack through van der Waals interactions. One-dimensional chains comprised of copper complexes are found in 2 and 4, and are held together by hydrogen bonds in 2 and acetate bridges between the copper cations in 4. The solution EPR spectra indicate that the copper(II) centres exist in isolated distorted square pyramidal (possibly square planar for 4) environments, while in the solid state there is evidence for the existence of weak exchange and dipole-dipole coupling for some complexes.
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Affiliation(s)
- Andrew C Warden
- School of Chemistry, Monash University, Victoria, 3800, Australia
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Jackson WG, Dickie AJ, McKeon JA, Spiccia L, Brudenell SJ, Hockless DCR, Willis AC. Synthesis, Structure, and Kinetics and Stereochemistry of Base-Catalyzed Hydrolysis of meso- and rac-[Co2(tmpdtne)Cl2]4+, Bis(pentaamine) Complexes Devoid of Deprotonatable NH Centers. Inorg Chem 2004; 44:401-9. [PMID: 15651887 DOI: 10.1021/ic0400888] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The bis(pentadentate) ligand tmpdtne binds two Co(II) centers, and the entity is readily oxidized to the dicobalt(III) derivative [Co(2)(tmpdtne)Cl(2)](4+) which has been separated into two isomeric forms. NMR studies establish these as meso and rac isomers arising from the different or same absolute configurations for the asym configuration about each Co(III) center. Each dinuclear ion base hydrolyses to the dihydroxo derivative [Co(2)(tmpdtne)(OH)(2)](4+) with retained asym configurations about each metal ion and also retained rac or meso configurations. The kinetics for the stepwise loss of the two Cl(-) ligands is uniphasic, and data are presented to show that the loss of the first chloride is rate determining and is followed by very rapid intramolecular and loss of the second Cl(-) via a hydroxo-bridged species to yield the observed dihydroxo derivative. Meso and rac forms of the latter have been crystallized. The X-ray crystal structure of the rac-dihydroxo complex is reported, and it establishes the configurations of all the complexes reported. The (1)H NMR spectra for the hydroxo ions show very high field Co-OH resonances (ca. delta-0.5 ppm) not observed previously for such ions, and this result is discussed in the context of published (1)H NMR data for bridged Co-OH-Co species. The base hydrolysis kinetics for the dichloro ions are first order in [OH(-)], and deprotonation at an alpha-CH(2) center (alpha to a pyridyl) is identified as the source of the catalysis, since there is no NH center available for deprotonation on the ligand. These data further support the new pseudoaminate base hydrolysis mechanism first reported in 2003. The values of k(OH) for the second-order base-catalyzed reaction are ca. 4.0 M(-1) s(-1) for both the rac and meso isomers, and these results are discussed in terms of the increased acidities of these 4+ cations compared to their 2+ ion counterparts.
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Affiliation(s)
- W Gregory Jackson
- School of Physical, Environmental and Mathematical Sciences, Chemistry, The University of New South Wales, Australian Defence Force Academy, Canberra, ACT, Australia 2600.
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Daier V, Biava H, Palopoli C, Shova S, Tuchagues JP, Signorella S. Synthesis, characterisation and catalase-like activity of dimanganese(III) complexes of 1,5-bis(5-X-salicylidenamino)pentan-3-ol (X=nitro and chloro). J Inorg Biochem 2004; 98:1806-17. [PMID: 15522408 DOI: 10.1016/j.jinorgbio.2004.08.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2004] [Revised: 07/08/2004] [Accepted: 08/09/2004] [Indexed: 10/26/2022]
Abstract
The dimanganese(III,III) complexes [Mn(2)(III)(5-NO(2)-salpentO)(mu-AcO)(mu-MeO)(methanol)(2)]Y (1: Y=Br, 2a: Y=I, 2b: Y=I(3)), [Mn(2)(III)(5-NO(2)-salpentO)(mu-AcO)(mu-MeO)(methanol)(ClO(4))] (3) and [Mn(2)(III)(5-Cl-salpentO)(mu-AcO)(mu-MeO)(methanol)(2)]Br (4), where salpentOH is the symmetrical Schiff base ligand 1,5-bis(salicylidenamino)pentan-3-ol, were synthesised and structurally characterized. Complex 2b crystallises in the monoclinic system, space group P2(1)/c, and exhibits Mn. . .Mn separation of 2.911 A. This Mn. . .Mn separation is very close to the other characterized (mu-alkoxo)(2)(mu-acetato)Mn(2)(III) complexes of X-salpentOH (X=MeO, Br and H) and reveals that the aromatic substituent has little influence on the geometric parameters of the bimetallic core. A correlation between the electronic character of the different ring substituents, the redox potentials of the dinuclear complexes and their catalase activity was evidenced. Complexes 1-4 show saturation kinetics with [H(2)O(2)] and the H(2)O(2) disproportionation involves redox cycling between the Mn(2)(III)/Mn(2)(IV) levels. The catalytic activity studies show that bound acetate is required for catalase activity and that the acetato and alkoxo bridges serve as internal bases facilitating the proton transfer coupled to oxidation of the metal centre.
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Affiliation(s)
- Verónica Daier
- Departamento de Química, Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Suipacha 531, 2000 Rosario, Argentina
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Li QX, Luo QH, Li YZ, Pan ZQ, Shen MC. Studies on Manganese(II) Complexes ofN-Benzimidazole-Functionalized 1,4,7-Triazacyclononane: Crystal Structures, Properties and Combined Superoxide Dismutase and Catalase Functions. Eur J Inorg Chem 2004. [DOI: 10.1002/ejic.200400157] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Li QX, Luo QH, Li YZ, Shen MC. A study on the mimics of Cu-Zn superoxide dismutase with high activity and stability: two copper(II) complexes of 1,4,7-triazacyclononane with benzimidazole groups. Dalton Trans 2004:2329-35. [PMID: 15278126 DOI: 10.1039/b404510f] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two copper(II) complexes [CuL(1)Cl]ClO(4) and [CuL(2)MeCN](ClO(4))(2)xH(2)O were synthesized (L(1)= 1-(benzimidazole-2-ylmethyl)-1,4,7-triazacyclononane, L(2)= 1,4-bis(benzimidazole-2-ylmethyl)-1,4,7-triazacyclonone). The benzimidazole groups were N-substituents of tacn, and the complexes are more stable than their parents. They are able to catalyse the dismutation of superoxide anion in aqueous solutions at physiological pH and in bovine serum albumin solution (0.5 mg ml(-1)). X-ray structure analysis and EPR and electronic spectra show that the structure of complex is more similar to the Cu(II) centre of Cu(2)Zn(2)SOD than that. Comparing with other Cu(II) complexes, the complex possesses both high SOD activity and highly thermodynamic stability.
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Affiliation(s)
- Qing-Xiang Li
- Coordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing 210093, P. R. China
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Mochizuki K, Numata Y. Synthesis of a novel nonsymmetrical bimacrocyclic ligand comprised of triaza and tetraaza macrocycles and its Dinckel(II) complexes. INORG CHEM COMMUN 2004. [DOI: 10.1016/j.inoche.2004.04.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Balland V, Anxolabéhère-Mallart E, Banse F, Rivière E, Bourcier S, Nierlich M, Girerd JJ. Synthesis, Structure and Characterizations in Solid State and Solution of Dinuclear Pentacoordinated FeII and MnII Complexes and of a Linear Tetranuclear FeIII Complex Obtained with the LigandN,N,N′,N′-Tetrakis[(6-methyl-2-pyridyl)methyl]propane-1,3-diamine. Eur J Inorg Chem 2004. [DOI: 10.1002/ejic.200300374] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Shaikh N, Panja A, Goswami S, Banerjee P, Vojtísek P, Zhang YZ, Su G, Gao S. Slow Magnetic Relaxation in a Mixed-Valence Mn(II/III) Complex: [MnII2(bispicen)2(μ3-Cl)2MnIII(Cl4Cat)2MnIII(Cl4Cat)2(H2O)2]∞. Inorg Chem 2004; 43:849-51. [PMID: 14753802 DOI: 10.1021/ic035072g] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A layered mixed-valence manganese complex, [Mn(II)(2)(bispicen)(2)(mu(3)-Cl)(2)Mn(III)(Cl(4)Cat)(2)Mn(III)(Cl(4)Cat)(2)(H(2)O)(2)](infinity), is synthesized and characterized structurally. It displays a slow magnetic relaxation and hysteresis effect.
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Affiliation(s)
- Nizamuddin Shaikh
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700 032, India
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Fry FH, Jensen P, Kepert CM, Spiccia L. Macrocyclic copper(II) and zinc(II) complexes incorporating phosphate esters. Inorg Chem 2003; 42:5637-44. [PMID: 12950212 DOI: 10.1021/ic026091d] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Slow evaporation of solutions prepared by adding either Cu(ClO(4))(2).6H(2)O or Zn(ClO(4))(2).6H(2)O to solutions containing appropriate proportions of Me(3)tacn (1,4,7-trimethyl-1,4,7-triazacyclononane) and sodium phenyl phosphate (Na(2)PhOPO(3)) gave dark blue crystals of [Cu(3)(Me(3)tacn)(3)(PhOPO(3))(2)](ClO(4))(2).(1)/(2)H(2)O (1) and colorless crystals of [Zn(2)(Me(3)tacn)(2)(H(2)O)(4)(PhOPO(3))](ClO(4))(2).H(2)O (2), respectively. Blue crystals of [Cu(tacn)(2)](BNPP)(2) (3) formed in an aqueous solution of [Cu(tacn)Cl(2)], bis(p-nitrophenyl phosphate) (BNPP), and HEPES buffer (pH 7.4). Compound 1 crystallizes in the triclinic space group P1 (No. 2) with a = 9.8053(2) A, b = 12.9068(2) A, c = 22.1132(2) A, alpha = 98.636(1) degrees, beta = 99.546(1) degrees, gamma = 101.1733(8) degrees, and Z = 2 and exhibits trinuclear Cu(II) clusters in which square pyramidal metal centers are capped by two phosphate esters located above and below the plane of the metal centers. The trinuclear cluster is asymmetric having Cu...Cu distances of 4.14, 4.55, and 5.04 A. Compound 2 crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 13.6248(2) A, b = 11.6002(2) A, c = 25.9681(4) A, beta = 102.0072(9) degrees, and Z = 4 and contains a dinuclear Zn(II) complex formed by linking two units of [Zn(Me(3)tacn)(OH(2))(2)](2+) by a single phosphate ester. Compound 3 crystallizes in the monoclinic space group C2/c (No. 15) with a = 24.7105(5) A, b = 12.8627(3) A, c = 14.0079(3) A, beta = 106.600(1) degrees, and Z = 4 and consists of mononuclear [Cu(tacn)(2)](2+) cations whose charge is balanced by the BNPP(-) anions.
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Affiliation(s)
- Fiona H Fry
- School of Chemistry, P.O. Box 23, Monash University, Victoria, 3800 Australia
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Marvaud V, Decroix C, Scuiller A, Guyard-Duhayon C, Vaissermann J, Gonnet F, Verdaguer M. Hexacyanometalate molecular chemistry: heptanuclear heterobimetallic complexes; control of the ground spin state. Chemistry 2003; 9:1677-91. [PMID: 12698426 DOI: 10.1002/chem.200390192] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Following a bottom-up approach to nanomaterials, we present a rational synthetic route from hexacyanometalates [M(CN)(6)](3-) (M=Cr(III), Co(III)) cores to well-defined heptanuclear complexes. By changing the nature of the metallic cations and using a localised orbital model it is possible to control and to tune the ground state spin value. Thus, with M=Cr(III), d(3), S=3/2, three heptanuclear species were built and characterised by mass spectrometry in solution, by single-crystal X-ray diffraction and by powder magnetic susceptibility measurements, [Cr(III)(CNbondM'L(n))(6)](9+) (M'=Cu(II), Ni(II), Mn(II), L(n)=polydentate ligand), showing spin ground states S(G)=9/2 [Cu(II)], with ferromagnetic interactions J(Cr,Cu)=+45 cm(-1), S(G)=15/2 [Ni(II)] and J(Cr,Ni)=+17.3 cm(-1), S(G)=27/2 [Mn(II)], with an antiferromagnetic interaction J(Cr,Mn)=-9 cm(-1), (interaction Hamiltonian H=-J(Cr,M) [S(Cr)Sigma(i)S(M)(i)], i=1-6). With M=Co(III), d(6), S=0, the heptanuclear analogues [Co(III)(CN-M'L(n))(6)](9+) (M'=Cu(II), Ni(II), Mn(II)) were similarly synthesised and studied. They present a singlet ground state and allow us to evaluate the weak antiferromagnetic coupling constant between two next-nearest neighbours M'-Co-M'.
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Affiliation(s)
- Valérie Marvaud
- Laboratoire de Chimie Inorganique et Matériaux Moléculaires, CNRS, UMR 7071, Université Pierre et Marie Curie, 75252 Paris Cedex 05, France.
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Deoghoria S, Sain S, Moulton B, Zaworotko MJ, Bera SK, Chandra SK. Synthesis, crystal structure and magnetic behavior of two new binuclear complexes bridged by a pentadentate ligand: [Ni2L2(NCS)2](ClO4)2 and [Ni2L2(NCO)2](ClO4)2 [L=pentadentate ligand]. Polyhedron 2002. [DOI: 10.1016/s0277-5387(02)01213-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Schmidt JAR, Arnold J. Reactions of a Triazacyclononane-Supported Tantalum−Lithium Bridging Alkylidene with Organic Substrates. Organometallics 2002. [DOI: 10.1021/om020175c] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Joseph A. R. Schmidt
- Department of Chemistry, University of California at Berkeley and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-1460
| | - John Arnold
- Department of Chemistry, University of California at Berkeley and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-1460
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Parker RJ, Spiccia L, Moubaraki B, Murray KS, Hockless DCR, Rae AD, Willis AC. Structure and magnetism of heptanuclear complexes formed on encapsulation of hexacyanoferrate(II) with the Mn(II) and Ni(II) complexes of 1,4-bis(2-pyridylmethyl)-1,4,7-triazacyclononane. Inorg Chem 2002; 41:2489-95. [PMID: 11978117 DOI: 10.1021/ic010711d] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The reaction of [Mn(dmptacn)OH(2)](2+) and [Ni(dmptacn)OH(2)](2+) (dmptacn = 1,4-bis(2-pyridylmethyl)-1,4,7-triazacyclononane) with each cyano ligand on ferricyanide results in the assembly of heteropolynuclear cations around the cyanometalate core and reduction of Fe(III) to Fe(II). In [[Mn(dmptacn)CN](6)Fe][ClO(4)](8) x 5H(2)O (1) and [[Ni(dmptacn)CN](6)Fe][ClO(4)](8) x 7H(2)O (2), ferrocyanide is encapsulated by either six Mn(II) or Ni(II) dmptacn moieties. These same products are obtained when ferrocyanide salts are used in the synthesis instead of ferricyanide. A binuclear complex, [[Mn(dmptacn)](2)CN][ClO(4)](3) (3), has also been formed from KCN and [Mn(dmptacn)OH(2)](2+). For both Mn(II) and Ni(II), the use of the pentadentate dmptacn ligand facilitates the formation of discrete cations in preference to networks or polymeric structures. 1 crystallizes in the trigonal space group R3 macro (No. 148) with a = 30.073(3) A, c = 13.303(4) A, and Z = 3 and is composed of heptanuclear [[Mn(dmptacn)CN](6)Fe](8+) cations whose charge is balanced by perchlorate counteranions. Weak H-bonding interactions between neighboring heptanuclear cations and some perchlorate counterions generate an infinite 1D chain of alternating [[Mn(dmptacn)CN](6)Fe](8+) and ClO(4)(-) ions running along the c-axis. Complex 3 crystallizes in the orthorhombic space group Pbcn (No. 60) with a = 16.225(3) A, b = 16.320(2) A, c = 18.052(3) A, and Z = 8 and is composed of binuclear [[Mn(dmptacn)](2)CN](3+) cations in which the cyano-bridged Mn(II) centers are in a distorted trigonal prismatic geometry. Variable temperature magnetic susceptibility measurements have revealed the presence of a weak ferromagnetic interaction between the paramagnetic Mn(II) centers in 1, mediated either by the -NC-Fe-CN- bridging units or by Mn-NH...ClO(4-)...NH-Mn intercluster pathways.
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Affiliation(s)
- Richard J Parker
- School of Chemistry, PO Box 23, Monash University, Victoria, 3800, Australia
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Boskovic C, Brechin EK, Streib WE, Folting K, Bollinger JC, Hendrickson DN, Christou G. Single-molecule magnets: a new family of Mn(12) clusters of formula [Mn(12)O(8)X(4)(O(2)CPh)(8)L(6)]. J Am Chem Soc 2002; 124:3725-36. [PMID: 11929262 DOI: 10.1021/ja012403k] [Citation(s) in RCA: 218] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of (NBu(n)(4))[Mn(8)O(6)Cl(6)(O(2)CPh)(7)(H(2)O)(2)] (1) with 2-(hydroxymethyl)pyridine (hmpH) or 2-(hydroxyethyl)pyridine (hepH) gives the Mn(II)(2)Mn(III)(10) title compounds [Mn(12)O(8)Cl(4)(O(2)CPh)(8)(hmp)(6)] (2) and [Mn(12)O(8)Cl(4)(O(2)CPh)(8)(hep)(6)] (3), respectively, with X = Cl. Subsequent reaction of 3 with HBr affords the Br(-) analogue [Mn(12)O(8)Br(4)(O(2)CPh)(8)(hep)(6)] (4). Complexes 2.2Et(2)O.4CH(2)Cl(2), 3.7CH(2)Cl(2), and 4.2Et(2)O.1.4CH(2)Cl(2) crystallize in the triclinic space group P1, monoclinic space group C2/c, and tetragonal space group I4(1)/a, respectively. Complexes 2 and 3 represent a new structural type, possessing isomeric [Mn(III)(10)Mn(II)(2)O(16)Cl(2)] cores but with differing peripheral ligation. Complex 4 is essentially isostructural with 3. A magnetochemical investigation of complex 2 reveals an S = 6 or 7 ground state and frequency-dependent out-of-phase signals in ac susceptibility studies that establish it as a new class of single-molecule magnet. These signals occur at temperatures higher than those observed for all previously reported single-molecule magnets that are not derived from [Mn(12)O(12)(O(2)CR)(16)(H(2)O)(x)]. A detailed investigation of forms of complex 2 with different solvation levels reveals that the magnetic properties of 2 are extremely sensitive to the latter, emphasizing the importance to the single-molecule magnet properties of interstitial solvent molecules in the samples. In contrast, complexes 3 and 4 are low-spin molecules with an S = 0 ground state.
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Affiliation(s)
- Colette Boskovic
- Department of Chemistry and the Molecular Structure Center, Indiana University, Bloomington, Indiana 47405-7102, USA
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Graham B, Spiccia L, Fallon GD, Hearn MTW, Mabbs FE, Moubaraki B, Murray KS. Structure and magnetic properties of tri- and hexa-nuclear hydroxo-bridged copper(ii) complexes formed by a trimacrocyclic derivative of 1,4,7-triazacyclononane. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b105595j] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Palopoli C, González-Sierra M, Robles G, Dahan F, Tuchagues JP, Signorella S. Synthesis and characterisation of dimanganese(iii) complexes of 1,5-bis(X-salicylidenamino)pentan-3-ol (X = 3- or 5-methoxy) and their catalytic activity towards hydrogen peroxide disproportionation. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b204566d] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Liao ZR, Zheng XF, Luo BS, Shen LR, Li DF, Liu HL, Zhao W. Synthesis, characterization and SOD-like activities of manganese-containing complexes with N,N,N′,N′-tetrakis(2′-benzimidazolyl methyl)-1,2-ethanediamine (EDTB). Polyhedron 2001. [DOI: 10.1016/s0277-5387(01)00891-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Warden A, Graham B, Hearn MT, Spiccia L. Synthesis of novel derivatives of 1,4,7-triazacyclononane. Org Lett 2001; 3:2855-8. [PMID: 11529774 DOI: 10.1021/ol016291d] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structure: see text]. The coordination environment of 1,4,7-triazacyclononane can be adapted, through sequential functionalization of two secondary amines, to generate ligands applicable in biomimetic studies. Two "amino acids" and an amino derivative have been prepared from 1,4,7-triazatricyclo[5.2.1.0(4,10)]decane. This synthon allows efficient attachment of one functional group to the macrocyclic ring, forming a monoamidinium salt. Hydrolysis generates a formyl derivative, which was further functionalized at the secondary amine and hydrolyzed in strong acid to generate ligands 1-3.
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Affiliation(s)
- A Warden
- Department of Chemistry, Monash University, 3800 Victoria, Australia
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Romero I, Collomb MN, Deronzier A, Llobet A, Perret E, Pécaut J, Le Pape L, Latour JM. A Novel Dimanganese(II) Complex with Two Chloride Bridges − A Two-Electron Oxidation System. Eur J Inorg Chem 2001. [DOI: 10.1002/1099-0682(20011)2001:1<69::aid-ejic69>3.0.co;2-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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