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Wang VCC, Maji S, Chen PPY, Lee HK, Yu SSF, Chan SI. Alkane Oxidation: Methane Monooxygenases, Related Enzymes, and Their Biomimetics. Chem Rev 2017; 117:8574-8621. [PMID: 28206744 DOI: 10.1021/acs.chemrev.6b00624] [Citation(s) in RCA: 249] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Methane monooxygenases (MMOs) mediate the facile conversion of methane into methanol in methanotrophic bacteria with high efficiency under ambient conditions. Because the selective oxidation of methane is extremely challenging, there is considerable interest in understanding how these enzymes carry out this difficult chemistry. The impetus of these efforts is to learn from the microbes to develop a biomimetic catalyst to accomplish the same chemical transformation. Here, we review the progress made over the past two to three decades toward delineating the structures and functions of the catalytic sites in two MMOs: soluble methane monooxygenase (sMMO) and particulate methane monooxygenase (pMMO). sMMO is a water-soluble three-component protein complex consisting of a hydroxylase with a nonheme diiron catalytic site; pMMO is a membrane-bound metalloenzyme with a unique tricopper cluster as the site of hydroxylation. The metal cluster in each of these MMOs harnesses O2 to functionalize the C-H bond using different chemistry. We highlight some of the common basic principles that they share. Finally, the development of functional models of the catalytic sites of MMOs is described. These efforts have culminated in the first successful biomimetic catalyst capable of efficient methane oxidation without overoxidation at room temperature.
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Affiliation(s)
- Vincent C-C Wang
- Institute of Chemistry, Academia Sinica , 128, Section 2, Academia Road, Nankang, Taipei 11529, Taiwan
| | - Suman Maji
- School of Chemical Engineering and Physical Sciences, Lovely Professional University , Jalandhar-Delhi G. T. Road (NH-1), Phagwara, Punjab India 144411
| | - Peter P-Y Chen
- Department of Chemistry, National Chung Hsing University , 250 Kuo Kuang Road, Taichung 402, Taiwan
| | - Hung Kay Lee
- Department of Chemistry, The Chinese University of Hong Kong , Shatin, New Territories, Hong Kong
| | - Steve S-F Yu
- Institute of Chemistry, Academia Sinica , 128, Section 2, Academia Road, Nankang, Taipei 11529, Taiwan
| | - Sunney I Chan
- Institute of Chemistry, Academia Sinica , 128, Section 2, Academia Road, Nankang, Taipei 11529, Taiwan.,Department of Chemistry, National Taiwan University , No. 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan.,Noyes Laboratory, 127-72, California Institute of Technology , 1200 East California Boulevard, Pasadena, California 91125, United States
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Dancs Á, May NV, Selmeczi K, Darula Z, Szorcsik A, Matyuska F, Páli T, Gajda T. Tuning the coordination properties of multi-histidine peptides by using a tripodal scaffold: solution chemical study and catechol oxidase mimicking. NEW J CHEM 2017. [DOI: 10.1039/c6nj03126a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Histidine-rich tripodal peptides form unique oligonuclear complexes with copper(ii), which exhibit efficient catecholase-like activity.
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Affiliation(s)
- Ágnes Dancs
- Department of Inorganic and Analytical Chemistry
- University of Szeged
- H-6720 Szeged
- Hungary
- Université de Lorraine – CNRS
| | - Nóra V. May
- Research Centre for Natural Sciences HAS
- H-1117 Budapest
- Hungary
| | - Katalin Selmeczi
- Université de Lorraine – CNRS
- UMR 7565 SRSMC
- 54506 Vandœuvre-lès-Nancy
- France
| | - Zsuzsanna Darula
- Institute of Biochemistry
- Biological Research Centre
- Hungarian Academy of Sciences
- H-6724 Szeged
- Hungary
| | - Attila Szorcsik
- MTA-SZTE Bioinorganic Chemistry Research Group
- H-6720 Szeged
- Hungary
| | - Ferenc Matyuska
- Department of Inorganic and Analytical Chemistry
- University of Szeged
- H-6720 Szeged
- Hungary
| | - Tibor Páli
- Institute of Biophysics
- Biological Research Centre
- Hungarian Academy of Sciences
- H-6724 Szeged
- Hungary
| | - Tamás Gajda
- Department of Inorganic and Analytical Chemistry
- University of Szeged
- H-6720 Szeged
- Hungary
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Matyuska F, May NV, Bényei A, Gajda T. Control of structure, stability and catechol oxidase activity of copper(ii) complexes by the denticity of tripodal platforms. NEW J CHEM 2017. [DOI: 10.1039/c7nj02013a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The speciation and catecholase-like activity of trinuclear complexes can be fine tuned by the denticity of tripodal platforms.
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Affiliation(s)
- Ferenc Matyuska
- Department of Inorganic and Analytical Chemistry
- University of Szeged
- H-6720 Szeged
- Hungary
| | - Nóra V. May
- Research Centre for Natural Sciences HAS
- H-1117 Budapest
- Hungary
| | - Attila Bényei
- Department of Pharmaceutical Chemistry
- University of Debrecen
- Debrecen H-4032
- Hungary
| | - Tamás Gajda
- Department of Inorganic and Analytical Chemistry
- University of Szeged
- H-6720 Szeged
- Hungary
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Allen SE, Walvoord RR, Padilla-Salinas R, Kozlowski MC. Aerobic copper-catalyzed organic reactions. Chem Rev 2013; 113:6234-458. [PMID: 23786461 PMCID: PMC3818381 DOI: 10.1021/cr300527g] [Citation(s) in RCA: 1228] [Impact Index Per Article: 111.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Scott E. Allen
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Ryan R. Walvoord
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Rosaura Padilla-Salinas
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Marisa C. Kozlowski
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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Morphology dependant oxidation of aromatic alcohols by new symmetrical copper(II) metallatriangles formed by self-assembly of a shared bis-benzimidazolyl diamide ligand. Inorganica Chim Acta 2013. [DOI: 10.1016/j.ica.2012.12.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Ghiladi RA, Rheingold AL, Siegler MA, Karlin KD. Synthesis and Characterization of New Trinuclear Copper Complexes. Inorganica Chim Acta 2012; 389:131-137. [PMID: 22773847 DOI: 10.1016/j.ica.2012.02.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
This report describes our approach towards modelling the copper cluster active sites of nitrous oxide reductase and the multicopper oxidases/oxygenases. We have synthesized two mesitylene-based trinucleating ligands, MesPY1 and MesPY2, which employ bis(2-picolyl)amine (PY1) and bis(2-pyridylethyl)amine (PY2) tridentate copper chelates, respectively. Addition of cuprous salts to these ligands leads to the isolation of tricopper(I) complexes [(Mes-PY1)Cu(I) (3)(CH(3)CN)(3)](ClO(4))(3)·0.25Et(2)O (1) and [(Mes-PY2)Cu(I) (3)](PF(6))(3) (3) Each of the three copper centers in 1 is most likely four-coordinate, with ligated acetonitrile as the fourth ligand; by contrast, the copper centers in 3 are three-coordinate, as determined by X-ray crystallography The synthesis of [(Mes-PY1)Cu(II) (3)(CH(3)CN)(2)(CH(3)OH)(2)](ClO(4))(6)·(CH(3)OH) (2) was accomplished by addition of three equivalents of the copper(II) salt, Cu(ClO(4))(2)·6H(2)O, to the ligand. The structure of 2 shows that two of the copper centers are tetracoordinate (with MeCN solvent ligation), but have additional weak axial (fifth ligand) interactions with the perchlorate anions; the third copper is unique in that it is coordinated by two MeOH solvent molecules, making it overall five-coordinate. For complexes 2 and 3, one copper ion center is located on the opposite side of the mesitylene plane as the other two. These observations, although in the solid state, must be taken into account for future studies where intramolecular tricopper(I)/O(2) (or other small molecules of interest) interactions in solution are desirable.
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Affiliation(s)
- Reza A Ghiladi
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA
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Mutti FG, Gullotti M, Casella L, Santagostini L, Pagliarin R, Andersson KK, Iozzi MF, Zoppellaro G. A new chiral, poly-imidazole N8-ligand and the related di- and tri-copper(ii) complexes: synthesis, theoretical modelling, spectroscopic properties, and biomimetic stereoselective oxidations. Dalton Trans 2011; 40:5436-57. [DOI: 10.1039/c0dt00669f] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Biomimetic modeling of copper complexes: a study of enantioselective catalytic oxidation on d-(+)-catechin and L-( - )-epicatechin with copper complexes. Bioinorg Chem Appl 2010:762029. [PMID: 18825268 PMCID: PMC2553160 DOI: 10.1155/2008/762029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2008] [Revised: 05/30/2008] [Accepted: 08/11/2008] [Indexed: 12/03/2022] Open
Abstract
The biomimetic catalytic oxidations of the dinuclear and trinuclear copper(II) complexes versus two catechols, namely, D-(+)-catechin
and L-( − )-epicatechin to give the corresponding quinones are reported. The unstable quinones were trapped by the nucleophilic reagent, 3-methyl-2-benzothiazolinone hydrazone (MBTH), and have been calculated the molar
absorptivities of the different quinones. The catalytic efficiency is moderate, as inferred by kinetic constants, but the complexes exhibit significant enantio-differentiating ability towards the catechols, albeit for the dinuclear complexes, this enantio-differentiating ability is lower. In all cases, the preferred enantiomeric substrate is D-(+)-catechin to respect the other catechol, because of the spatial disposition of this substrate.
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Mutti FG, Zoppellaro G, Gullotti M, Santagostini L, Pagliarin R, Andersson KK, Casella L. Biomimetic Modelling of Copper Enzymes: Synthesis, Characterization, EPR Analysis and Enantioselective Catalytic Oxidations by a New Chiral Trinuclear Copper(II) Complex. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200800899] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Sreenivasulu B. Diphenoxo-Bridged Copper(II) Complexes of Reduced Schiff Base Ligands as Functional Models for Catechol Oxidase. Aust J Chem 2009. [DOI: 10.1071/ch09263] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The design and development of synthetic analogues for the active dicopper(ii) sites of catechol oxidase, with the help of binucleating ligands in particular, is an attractive strategy to generate relevant information on structure–function relationships. Dicopper(ii) complexes of different yet closely related series of reduced Schiff base ligands (N-(2-hydroxybenzyl)-amino acids; N-(2-hydroxybenzyl)-amino amides, N-(2-hydroxybenzyl)-aminomethane or ethanesulfonic acids, and N-(2-hydroxy-5-substituted-benzyl)-cyclopentane or hexanecarboxylic acids) derived from various substituted salicylaldehydes and natural or unnatural amino acids or amides explored as functional models for the Type 3 copper enzyme catecholase oxidase are reviewed in the present paper. The catalytic activity of different series of dicopper(ii) complexes to oxidize the model substrate 3,5-di-tert-butylcatechol to the corresponding 3,5-di-tert-butylquinone is discussed with respect to the various ligand properties such as the length and chelating ability of the amino acid side-arm of the ligands, conformation of the ligand, nature of the donor groups on the amino acid backbone and role of different para-substituents. This article provides a short review summarizing the trend observed in the catecholase activity of different series of dicopper(ii) complexes investigated in our laboratory.
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Brown EC, Johnson B, Palavicini S, Kucera BE, Casella L, Tolman WB. Modular syntheses of multidentate ligands with variable N-donors: applications to tri- and tetracopper(i) complexes. Dalton Trans 2007:3035-42. [PMID: 17622421 DOI: 10.1039/b705806c] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A general method for the preparation of multidentate ligands comprised of a multi-imine platform derived from 1,1,1-tris(aminomethyl)ethane or tris(aminoethyl)amine connected to bi- and tridentate N-donor chelates has been developed. The feasibility of the method has been demonstrated through the synthesis and characterization of a large set of these ligand types. Complexation to Cu(I) was accomplished for several cases, yielding tri- and tetracopper(I) complexes that have been characterized in solution by NMR spectroscopy and conductivity, and in the solid state by elemental analysis, mass spectrometry, and/or X-ray crystallography. These complexes are potentially useful for modeling multicopper protein active sites.
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Affiliation(s)
- Eric C Brown
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455, USA
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Koval IA, Selmeczi K, Belle C, Philouze C, Saint-Aman E, Gautier-Luneau I, Schuitema AM, van Vliet M, Gamez P, Roubeau O, Lüken M, Krebs B, Lutz M, Spek AL, Pierre JL, Reedijk J. Catecholase Activity of a Copper(II) Complex with a Macrocyclic Ligand: Unraveling Catalytic Mechanisms. Chemistry 2006; 12:6138-50. [PMID: 16832797 DOI: 10.1002/chem.200501600] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We report the structure, properties and a mechanism for the catecholase activity of a tetranuclear carbonato-bridged copper(II) cluster with the macrocyclic ligand [22]pr4pz (9,22-dipropyl-1,4,9,14,17,22,27,28,29, 30-decaazapentacyclo[22.2.1.1(4,7).1(11,14). 1(17,20)]triacontane-5,7(28),11(29),12,18, 20(30),24(27),25-octaene). In this complex, two copper ions within a macrocyclic unit are bridged by a carbonate anion, which further connects two macrocyclic units together. Magnetic susceptibility studies have shown the existence of a ferromagnetic interaction between the two copper ions within one macrocyclic ring, and a weak antiferromagnetic interaction between the two neighboring copper ions of two different macrocyclic units. The tetranuclear complex was found to be the major compound present in solution at high concentration levels, but its dissociation into two dinuclear units occurs upon dilution. The dinuclear complex catalyzes the oxidation of 3,5-di-tert-butylcatechol to the respective quinone in methanol by two different pathways, one proceeding via the formation of semiquinone species with the subsequent production of dihydrogen peroxide as a byproduct, and another proceeding via the two-electron reduction of the dicopper(II) center by the substrate, with two molecules of quinone and one molecule of water generated per one catalytic cycle. The occurrence of the first pathway was, however, found to cease shortly after the beginning of the catalytic reaction. The influence of hydrogen peroxide and di-tert-butyl-o-benzoquinone on the catalytic mechanism has been investigated. The crystal structures of the free ligand and the reduced dicopper(I) complex, as well as the electrochemical properties of both the Cu(II) and the Cu(I) complexes are also reported.
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Affiliation(s)
- Iryna A Koval
- Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
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Company A, Gómez L, López Valbuena JM, Mas-Ballesté R, Benet-Buchholz J, Llobet A, Costas M. Isomeric Molecular Rectangles Resulting from Self-Assembly of Dicopper Complexes of Macrocyclic Ligands. Inorg Chem 2006; 45:2501-8. [PMID: 16529471 DOI: 10.1021/ic051759k] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dinuclear copper complexes containing hexaazacyclophane macrocyclic ligands react with the disodium salt of terephthalic acid resulting in the self-assembly of rectangular molecules with the general formula [(Cu2L)2(p-(O2CC6H4CO2)2)]X4, where X = CF3SO3 and ClO4 (3X4, L = Me2p and 4X4, L = Me2m). Tetranuclear complexes 3(CF3SO3)4 (as polymorphs 3a and 3b) and 4(ClO4)4 have been characterized by single-crystal X-ray diffraction analysis providing definitive proof of their structure as well as their metrical parameters. 3a contains, in its unit cell, two isomeric cationic units (3asyn and 3aanti) that differ in the relative position of the two O carboxylate atoms which bind to the Cu atoms of the different macrocyclic complexes, leading to boxes with different metrical parameters. ESI-MS analyses of solutions of the tetranuclear complexes 3(CF3SO3)4 and 4(CF3SO3)4 exhibit cluster ions which match the solid state formulation, thus demonstrating that the cages are retained in solution.
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Affiliation(s)
- Anna Company
- Departament de Química, Universitat de Girona, Campus de Montilivi, E-17071 Girona, Spain
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Koval IA, Gamez P, Belle C, Selmeczi K, Reedijk J. Synthetic models of the active site of catechol oxidase: mechanistic studies. Chem Soc Rev 2006; 35:814-40. [PMID: 16936929 DOI: 10.1039/b516250p] [Citation(s) in RCA: 420] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ability of copper proteins to process dioxygen at ambient conditions has inspired numerous research groups to study their structural, spectroscopic and catalytic properties. Catechol oxidase is a type-3 copper enzyme usually encountered in plant tissues and in some insects and crustaceans. It catalyzes the conversion of a large number of catechols into the respective o-benzoquinones, which subsequently auto-polymerize, resulting in the formation of melanin, a dark pigment thought to protect a damaged tissue from pathogens. After the report of the X-ray crystal structure of catechol oxidase a few years earlier, a large number of publications devoted to the biomimetic modeling of its active site appeared in the literature. This critical review (citing 114 references) extensively discusses the synthetic models of this enzyme, with a particular emphasis on the different approaches used in the literature to study the mechanism of the catalytic oxidation of the substrate (catechol) by these compounds. These are the studies on the substrate binding to the model complexes, the structure-activity relationship, the kinetic studies of the catalytic oxidation of the substrate and finally the substrate interaction with (per)oxo-dicopper adducts. The general overview of the recognized types of copper proteins and the detailed description of the crystal structure of catechol oxidase, as well as the proposed mechanisms of the enzymatic cycle are also presented.
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Affiliation(s)
- Iryna A Koval
- Leiden Institute of Chemistry, Leiden University, P. O. Box 9502, 2300 RA Leiden, Netherlands
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Battaini G, Granata A, Monzani E, Gullotti M, Casella L. Biomimetic Oxidations by Dinuclear and Trinuclear Copper Complexes. ADVANCES IN INORGANIC CHEMISTRY 2006. [DOI: 10.1016/s0898-8838(05)58005-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Infinite zig-zag and cyclic-tetranuclear isomeric imidazolate-bridged polynuclear copper(II) complexes: Magnetic properties, catalytic activity and electrospray mass and tandem mass spectrometry characterization. Inorganica Chim Acta 2005. [DOI: 10.1016/j.ica.2005.06.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Gullotti M, Santagostini L, Pagliarin R, Granata A, Casella L. Synthesis and characterization of new chiral octadentate nitrogen ligands and related copper(II) complexes as catalysts for stereoselective oxidation of catechols. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.molcata.2005.03.031] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Mimmi MC, Gullotti M, Santagostini L, Battaini G, Monzani E, Pagliarin R, Zoppellaro G, Casella L. Models for biological trinuclear copper clusters. Characterization and enantioselective catalytic oxidation of catechols by the copper(ii) complexes of a chiral ligand derived from (S)-(−)-1,1′-binaphthyl-2,2′-diamine. Dalton Trans 2004:2192-201. [PMID: 15249957 DOI: 10.1039/b402539c] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dinuclear and trinuclear Cu(II) complexes of an octadentate ligand derived from (S)-1,1'-binaphthyl-2,2'-diamine have been prepared and characterized by UV/Vis, CD, EPR and NMR spectroscopy. The ligand contains two tridentate aminobis(benzimidazole) donor arms connected to a central bidentate diaminobinaphthyl linker, which hosts the chiral unit. In the dinuclear Cu complex the ligation occurs essentially within the tridentate arms of the ligand. The two Cu centers are EPR nonequivalent and noninteracting. The EPR data suggests that one of the Cu ions additionally interacts with one of the tertiary aminonaphthyl donors. In the trinuclear complex the two aminonaphthyl donors bind the third Cu ion. The EPR spectrum of this complex shows the signal for a mononuclear Cu(II) center bound to a tridentate arm, while the remaining two Cu(II) centers are coupled through hydroxo groups. The CD spectrum shows that in the free ligand a severe reduction of the dihedral angle between the naphthyl groups from the strain free range occurs. This conformation is stabilized by ring stacking interactions with the benzimidazole groups. On complex formation this interaction is removed because the benzimidazole groups are involved in metal binding. In the dinuclear Cu complex the conformation of the binaphthyl chromophore probably approaches the strain free range, while in the trinuclear Cu complex a marked flattening of the dihedral angle between the two naphthyl rings occurs. Both complexes are active catalysts in the oxidation of L-/D-Dopa derivatives to quinones. High enantioselectivity is observed in the oxidation of L-/D-Dopa methyl ester catalyzed by the dinuclear Cu complex, which exhibits strong preference for the d enantiomer. The enantioselectivity is largely lost for the trinuclear Cu complex.
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Affiliation(s)
- Maria Chiara Mimmi
- Dipartimento di Chimica Inorganica, Metallorganica e Analitica, Università di Milano, Istituto ISTM-CNR, Milano, Italy
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Mimmi M, Gullotti M, Santagostini L, Pagliarin R, De Gioia L, Monzani E, Casella L. Synthesis and Conformational Studies of a Chiral Octadentate Ligand Derived from (R)-1,1′-Binaphthyl-2,2′-diamine and its Dinuclear Zinc(II) and Nickel(II) Complexes. Eur J Inorg Chem 2003. [DOI: 10.1002/ejic.200300103] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Catechol oxidase model compounds based on aminocarbohydrates: new structure types and investigations on the catalytic reaction. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1381-1169(03)00190-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Comparative kinetic studies on tyrosinase-like catalytic activity of dinuclear imidazole-containing copper(II) complexes. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1381-1169(03)00003-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Andrade Alves W, Afonso de Almeida Filho S, Helena de Almeida Santos R, Maria Da Costa Ferreira A. Diimine copper(II) complexes as building blocks for microporous catalytic materials. INORG CHEM COMMUN 2003. [DOI: 10.1016/s1387-7003(02)00757-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Mohamed G, El-Gamel NE, Teixidor F. Complexes of 2-(2-benzimidazolylazo)-4-acetamidophenol, a phenoldiazenyl-containing ligand. Could this be a moiety suitable for Zn and Cd extraction? Polyhedron 2001. [DOI: 10.1016/s0277-5387(01)00867-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Monzani E, Battaini G, Perotti A, Casella L, Gullotti M, Santagostini L, Nardin G, Randaccio L, Geremia S, Zanello P, Opromolla G. Mechanistic, Structural, and Spectroscopic Studies on the Catecholase Activity of a Dinuclear Copper Complex by Dioxygen. Inorg Chem 1999. [DOI: 10.1021/ic990397b] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Santagostini L, Gullotti M, Pagliarin R, Bianchi E, Casella L, Monzani E. Functional mimics of copper enzymes. Synthesis and stereochemical properties of the copper(II) complexes of a trinucleating ligand derived from l-histidine. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0957-4166(98)00505-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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