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Radhakrishna L, Sheokand S, Mondal D, Balakrishna MS. Structural Diversity and Rare η 1 Cu-C Interactions in Cu I Complexes of 1,2,3-Triazole-Functionalized Bisphosphines. Inorg Chem 2024; 63:9919-9930. [PMID: 38755737 DOI: 10.1021/acs.inorgchem.4c00951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
This manuscript describes the synthesis of copper complexes of 1,2,3-triazolyl-phosphines: o-Ph2P(C6H4){1,2,3-N3CC6H5)C(PPh2)} (L1), (C6H5){1,2,3-N3C(C6H4(o-PPh2))-C(PPh2)} (L2), 3-Ph2P(C5H3N){1,2,3-N3C(C6H5)C(PPh2)} (L3), o-Ph2P(C6H4){1,2,3-N3C(C5H5N)C(PPh2)} (L4), and {(3,5-Ph2PC6H4-o)21,2,3-N3CCH} (L5). The reactions of L1-L3 with CuI salts afforded dimeric complexes having the general formula [Cu2(μ -X)2L2] (L = L1, X = Cl, Br and I: 1 - 3; L= L2, X = Cl, Br and I: 4- 6; L = L3; X = Cl, Br, and I: 7-9). The reaction of L4 with CuI in a 1:2 molar ratio afforded 1D-coordination polymer [{(CuI)2{o-Ph2P(C6H4){1,2,3-N3C(C5H5N)C(PPh2)}-μ-((k1-N)(k2-P,P))}}]n (10). The reaction of L5 with cuprous halides (CuX) (X = Br, I) yielded mononuclear complexes [CuX{(3,5-Ph2PC6H4-o)21,2,3-N3CCH}-κ2P,P] (X = Br, 12; I, 13). Crystal structures of complexes 12 and 13 showed close interactions between CuI and the triazole C7 carbon. These relatively short Cu···C7 separations may be due to the η1-C interaction (dπ-pπ bond) between the triazolic carbon atom (via pz orbital) and CuI or three-centered two-electron interaction between CuI and the triazolic C-H bond. The existence of the Cu···C interaction was further evinced by the QTAIM analysis in compounds 12 and 13.
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Affiliation(s)
- Latchupatula Radhakrishna
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Powai 400076, India
| | - Sonu Sheokand
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Powai 400076, India
| | - Dipanjan Mondal
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Powai 400076, India
| | - Maravanji S Balakrishna
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Powai 400076, India
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2
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Kunchur HS, Sonawane SC, Saini P, Ramakrishnan S, Balakrishna MS. Copper(I) Complexes of Amide Functionalized Bisphosphine: Proximity Enhanced Metal-Ligand Cooperativity and Its Catalytic Advantage in C( sp3)-H Bond Activation of Unactivated Cycloalkanes in Dehydrogenative Carboxylation Reactions. Inorg Chem 2023. [PMID: 38031668 DOI: 10.1021/acs.inorgchem.3c01022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
The reactions of amide functionalized bisphosphine, o-Ph2PC6H4C-(O)N(H)C6H4PPh2-o (1) (BalaHariPhos), with copper salts is described. Treatment of 1 with CuX in a 1:1 molar ratio yielded chelate complexes of the type [CuX{(o-Ph2PC6H4C(O)N(H)C6H4PPh2-o)}-κ2-P,P] (X = Cl, 2; Br, 3; and I, 4), which on subsequent treatment with KOtBu resulted in a dimeric complex [Cu(o-Ph2PC6H4C(O)(N)C6H4PPh2-o)]2 (5). Interestingly, complexes 2-4 showed weak N-H···Cu interactions. These weak H-bonding interactions are studied in detail both experimentally and computationally. Also, CuI complexes 2-5 were employed in the oxidative dehydrogenative carboxylation (ODC) of unactivated cycloalkanes in the presence of carboxylic acids to form the corresponding allylic esters. Among complexes 2-5, halide-free dimeric CuI complex 5 showed excellent metal-ligand cooperativity in the oxidative dehydrogenative carboxylation (ODC) in the presence of carboxylic acids to form the corresponding allylic esters through C(sp3)-H bond activation of unactivated cycloalkanes. Mechanistic details of the catalytic process were established by isolating the precatalyst [Cu{(o-Ph2PC6H4C(O)(NH)C6H4PPh2-o)-κ2-P,P}(OOCPh)] (6) and fully characterized by mass spectrometry, NMR data, and single-crystal X-ray analysis. Density functional theory-based calculations further provided a quantitative understanding of the energetics of a series of H atom transfer steps occurring in the catalytic cycle.
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Affiliation(s)
- Harish S Kunchur
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Sachin C Sonawane
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Prateek Saini
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | | | - Maravanji S Balakrishna
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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3
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Zhong X, Bouchey CJ, Kabir E, Tolman WB. Using a monocopper-superoxo complex to prepare multicopper-peroxo species relevant to proposed enzyme intermediates. J Inorg Biochem 2021; 222:111498. [PMID: 34120095 PMCID: PMC9835715 DOI: 10.1016/j.jinorgbio.2021.111498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/29/2021] [Accepted: 05/29/2021] [Indexed: 01/16/2023]
Abstract
With the goal of generating a (peroxo)tricopper species analogous to the Peroxy Intermediate proposed for multicopper oxidases, solutions of the copper-superoxide complex [K(Krypt)][LCuO2] (L = N,N'-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamide, Krypt = 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) were reacted with the dicopper(I) complex [(TPBN)Cu2(MeCN)2][PF6]2 at -70 °C (TPBN = N,N,N',N'-tetrakis-(2-pyridylmethyl)-1,4-diaminobutane). A metastable intermediate formed, which on the basis of UV-vis, EPR, and resonance Raman spectroscopy was proposed to derive from reaction of two equivalents of the copper-superoxide with one equivalent of the dicopper(I) complex to yield a complex with two (peroxo)dicopper moieties rather than the desired (peroxo)tricopper PI model. A similar intermediate formed upon reaction of [K(Krypt)][LCuO2] with [(BPMA)Cu(MeCN)][PF6] (BPMA = N,N-bis(2-pyridylmethyl)-methyl-amine), which contained the same donor set as provided by TPBN. Comparison of resonance Raman data and consideration of structural preferences for LCuX species led to hypothesis of a μ-η1:η2-peroxo structure for both intermediates.
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Affiliation(s)
- Xinzhe Zhong
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, MO 63130-4899, United States of America
| | - Caitlin J. Bouchey
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, MO 63130-4899, United States of America,Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455, United States of America
| | - Evanta Kabir
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, MO 63130-4899, United States of America
| | - William B. Tolman
- Department of Chemistry, Washington University in St. Louis, One Brookings Hall, Campus Box 1134, St. Louis, MO 63130-4899, United States of America,Corresponding author. (W.B. Tolman)
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4
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Abe T, Shiota Y, Itoh S, Yoshizawa K. Theoretical rationalization for the equilibrium between (μ-η 2:η 2-peroxido)Cu IICu II and bis(μ-oxido)Cu IIICu III complexes: perturbational effects from ligand frameworks. Dalton Trans 2020; 49:6710-6717. [PMID: 32368776 DOI: 10.1039/d0dt01001d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
DFT calculations are carried out to investigate the geometric effects of the supporting ligands in the relative energies of the (μ-η2:η2-peroxido)CuIICuII complex 1 and the bis(μ-oxido)CuIIICuIII complex 2. The N3-tridentate ligand bearing acyclic propane diamine framework La preferentially provided 1, whereas the N3-tridentate ligand with cyclic diamine framework such as 1,4-diazacycloheptane Lb gave 2 after the oxygenation of the corresponding CuI complexes as reported previously [S. Itoh, et al., Inorg. Chem., 2014, 53, 8786-8794]. Calculations at the B3LYP*-D3 level of theory can reasonably explain the experimental results in relative energies, structures and harmonic frequencies of 1 and 2. Perturbational effects of the diamine chelates of La and Lb especially on the equilibrium of 1 and 2 are investigated in detail. In the range from 2.30 Å to 3.40 Å of the N-N distance in the diamine moiety, 1 is more stable than 2 by 8.4 kcal mol-1 at the distance of 3.40 Å. Calculated potential energies indicate that the decrease in the N-N distance is associated with a decrease in energy of 2, leading that 2 can be most stabilized at the N-N distance of 2.60 Å. Furthermore, molecular orbitals analyses are performed to explain that the energy gaps between the σ* orbital of the O-O bond and the dx2-y2 orbitals of the CuII ions of 1 get small as the diamine moiety is shrunk, leading to facilitate the O-O bond cleavage from 1 to 2.
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Affiliation(s)
- Tsukasa Abe
- Institute for Materials Chemistry and Engineering and IRCCS, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, Japan.
| | - Yoshihito Shiota
- Institute for Materials Chemistry and Engineering and IRCCS, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, Japan.
| | - Shinobu Itoh
- Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, Japan
| | - Kazunari Yoshizawa
- Institute for Materials Chemistry and Engineering and IRCCS, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, Japan.
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5
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Suktanarak P, Ruangpornvisuti V, Suksai C, Tuntulani T, Leeladee P. Stabilisation of copper(i) polypyridyl complexes toward aerobic oxidation by zinc(ii) in combination with acetate anions: a facile approach and its application in ascorbic acid sensing in aqueous solution. Dalton Trans 2019; 48:997-1005. [DOI: 10.1039/c8dt03580f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A new approach to stabilise Cu(i) complexes in aqueous solution using Zn(ii) acetate was demonstrated.
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Affiliation(s)
- Pattira Suktanarak
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
| | | | - Chomchai Suksai
- Department of Chemistry and Centre for Innovation in Chemistry
- Faculty of Science
- Burapha University
- Chonburi 20131
- Thailand
| | - Thawatchai Tuntulani
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
| | - Pannee Leeladee
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
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6
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Suktanarak P, Watchasit S, Chitchak K, Plainpan N, Chainok K, Vanalabhpatana P, Pienpinijtham P, Suksai C, Tuntulani T, Ruangpornvisuti V, Leeladee P. Tuning the reactivity of copper complexes supported by tridentate ligands leading to two-electron reduction of dioxygen. Dalton Trans 2018; 47:16337-16349. [DOI: 10.1039/c8dt03183e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dinuclear copper complex with tridentate ligand and anthracene linkage catalyses 2-electron reduction of O2.
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Affiliation(s)
- Pattira Suktanarak
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
| | - Sarayut Watchasit
- Nuclear Magnetic Resonance Spectroscopic Laboratory
- Science Innovation Facility
- Faculty of Science
- Burapha University
- Chonburi 20131
| | - Kantima Chitchak
- Program of Petrochemistry and Polymer Science
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
| | - Nukorn Plainpan
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
| | - Kittipong Chainok
- Materials and Textile Technology
- Faculty of Science and Technology
- Thammasat University
- Pathum Thani 12121
- Thailand
| | | | | | - Chomchai Suksai
- Department of Chemistry and Center for Innovation in Chemistry
- Faculty of Science
- Burapha University
- Chonburi 20131
- Thailand
| | - Thawatchai Tuntulani
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
| | | | - Pannee Leeladee
- Department of Chemistry
- Faculty of Science
- Chulalongkorn University
- Bangkok 10330
- Thailand
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7
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Elwell CE, Gagnon NL, Neisen BD, Dhar D, Spaeth AD, Yee GM, Tolman WB. Copper-Oxygen Complexes Revisited: Structures, Spectroscopy, and Reactivity. Chem Rev 2017; 117:2059-2107. [PMID: 28103018 PMCID: PMC5963733 DOI: 10.1021/acs.chemrev.6b00636] [Citation(s) in RCA: 445] [Impact Index Per Article: 63.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A longstanding research goal has been to understand the nature and role of copper-oxygen intermediates within copper-containing enzymes and abiological catalysts. Synthetic chemistry has played a pivotal role in highlighting the viability of proposed intermediates and expanding the library of known copper-oxygen cores. In addition to the number of new complexes that have been synthesized since the previous reviews on this topic in this journal (Mirica, L. M.; Ottenwaelder, X.; Stack, T. D. P. Chem. Rev. 2004, 104, 1013-1046 and Lewis, E. A.; Tolman, W. B. Chem. Rev. 2004, 104, 1047-1076), the field has seen significant expansion in the (1) range of cores synthesized and characterized, (2) amount of mechanistic work performed, particularly in the area of organic substrate oxidation, and (3) use of computational methods for both the corroboration and prediction of proposed intermediates. The scope of this review has been limited to well-characterized examples of copper-oxygen species but seeks to provide a thorough picture of the spectroscopic characteristics and reactivity trends of the copper-oxygen cores discussed.
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Affiliation(s)
- Courtney E Elwell
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Nicole L Gagnon
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Benjamin D Neisen
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Debanjan Dhar
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Andrew D Spaeth
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - Gereon M Yee
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - William B Tolman
- Department of Chemistry, Center for Metals in Biocatalysis, University of Minnesota , 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
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8
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Hoffmann A, Wern M, Hoppe T, Witte M, Haase R, Liebhäuser P, Glatthaar J, Herres-Pawlis S, Schindler S. Hand in Hand: Experimental and Theoretical Investigations into the Reactions of Copper(I) Mono- and Bis(guanidine) Complexes with Dioxygen. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600906] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Alexander Hoffmann
- Institut für Anorganische Chemie; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Miriam Wern
- Institut für Anorganische und Analytische Chemie; Justus-Liebig-Universität Gießen; Heinrich-Buff-Ring 17 35392 Gießen Germany
| | - Tobias Hoppe
- Institut für Anorganische und Analytische Chemie; Justus-Liebig-Universität Gießen; Heinrich-Buff-Ring 17 35392 Gießen Germany
| | - Matthias Witte
- Institut für Anorganische Chemie; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Roxana Haase
- Department Chemie; Universität Paderborn; Warburger Str. 100 33098 Paderborn Germany
| | - Patricia Liebhäuser
- Institut für Anorganische Chemie; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Jörg Glatthaar
- Institut für Organische Chemie; Heinrich-Buff-Ring 17 35392 Gießen Germany
| | - Sonja Herres-Pawlis
- Institut für Anorganische Chemie; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Siegfried Schindler
- Institut für Anorganische und Analytische Chemie; Justus-Liebig-Universität Gießen; Heinrich-Buff-Ring 17 35392 Gießen Germany
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9
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Acid-base and redox equilibria of a tris(2-pyridylmethyl)amine copper complex; their effects on electrocatalytic oxygen reduction by the complex. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.05.166] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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10
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Kafentzi MC, Orio M, Réglier M, Yao S, Kuhlmann U, Hildebrandt P, Driess M, Simaan AJ, Ray K. Changing the chemical and physical properties of high valent heterobimetallic bis-(μ-oxido) Cu–Ni complexes by ligand effects. Dalton Trans 2016; 45:15994-16000. [DOI: 10.1039/c6dt02391f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two new heterobimetallic [LNiO2Cu(RPY2)]+ (RPY2 = N-substituted bis 2-pyridyl(ethylamine) ligands with R = indane, 3a or R = Me, 3b) complexes have been spectroscopically trapped at low temperatures.
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Affiliation(s)
| | - Maylis Orio
- Aix Marseille Univ
- CNRS
- Centrale Marseille
- iSm2
- Marseille
| | | | - Shenglai Yao
- Department of Chemistry
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | - Uwe Kuhlmann
- Department of Chemistry
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | - Peter Hildebrandt
- Department of Chemistry
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | - Matthias Driess
- Department of Chemistry
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | | | - Kallol Ray
- Department of Chemistry
- Humboldt-Universität zu Berlin
- 12489 Berlin
- Germany
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11
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Asahi M, Yamazaki SI, Itoh S, Ioroi T. Electrochemical reduction of dioxygen by copper complexes with pyridylalkylamine ligands dissolved in aqueous buffer solution: the relationship between activity and redox potential. Dalton Trans 2014; 43:10705-9. [DOI: 10.1039/c4dt00606b] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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12
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Affiliation(s)
- Robert D. Pike
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795,
United States
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13
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Liu X, Pattacini R, Deglmann P, Braunstein P. Do Short C–H–M (M = Cu(I), Ag(I)) Distances Represent Agostic Interactions in Pincer-Type Complexes? Unusual NHC Transmetalation from Cu(I) to Ag(I). Organometallics 2011. [DOI: 10.1021/om200033m] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Lee Y, Lee DH, Park GY, Lucas HR, Narducci Sarjeant AA, Kieber-Emmons MT, Vance MA, Milligan AE, Solomon EI, Karlin KD. Sulfur donor atom effects on copper(I)/O(2) chemistry with thioanisole containing tetradentate N(3)S ligand leading to μ-1,2-peroxo-dicopper(II) species. Inorg Chem 2011; 49:8873-85. [PMID: 20822156 DOI: 10.1021/ic101041m] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To better understand the effect of thioether coordination in copper-O(2) chemistry, the tetradentate N(3)S ligand L(ASM) (2-(methylthio)-N,N-bis((pyridin-2-yl)methyl)benzenamine) and related alkylether ligand L(EOE) (2-ethoxy-N,N-bis((pyridin-2-yl)methyl)ethanamine) have been studied. The corresponding copper(I) complexes, [(L(ASM))Cu(I)](+) (1a) and [(L(EOE))Cu(I)](+) (3a), were studied as were the related compound [(L(ESE))Cu(I)](+) (2a, L(ESE) = (2-ethylthio-N,N-bis((pyridin-2-yl)methyl)ethanamine). The X-ray structure of 1a and its solution conductivity reveal a monomeric molecular structure possessing thioether coordination which persists in solution. In contrast, the C-O stretching frequencies of the derivative Cu(I)-CO complexes reveal that for these complexes, the modulated ligand arms, whether arylthioether, alkylthioether, or ether, are not coordinated to the cuprous ion. Electrochemical data for 1a and 2a in CH(3)CN and N,N-dimethylformamide (DMF) show the thioanisole moiety to be a poor electron donor compared to alkylthioether (1a is ∼200 mV more positive than 2a). The structures of [(L(ASM))Cu(II)(CH(3)OH)](2+) (1c) and [(L(ESE))Cu(II)(CH(3)OH)](2+) (2c) have also been obtained and indicate nearly identical copper coordination environments. Oxygenation of 1a at reduced temperature gives a characteristic deep blue intermediate [{(L(ASM))Cu(II)}(2)(O(2)(2-))](2+) (1b(P)) with absorption features at 442 (1,500 M(-1) cm(-1)), 530 (8,600 M(-1) cm(-1)), and 605 nm (10,400 M(-1) cm(-1)); these values compare well to the ligand-to-metal charge-transfer (LMCT) transitions previously reported for [{(L(ESE))Cu(II)}(2)(O(2)(2-))](2+) (2b(P)). Resonance Raman data for [{(L(ASM))Cu(II)}(2)(O(2)(2-))](2+) (1b(P)) support the formation of μ-1,2-peroxo species ν(O-O) = 828 cm(-1)(Δ((18)O(2)) = 48), ν(sym)(Cu-O) = 547 cm(-1) (Δ((18)O(2)) = 23), and ν(asym)(Cu-O) = 497 cm(-1) (Δ((18)O(2)) = 22) and suggest the L(ASM) ligand is a poorer electron donor to copper than is L(ESE). In contrast, the oxygenation of [(L(EOE))Cu(I)](+) (3a), possessing an ether donor as an analogue of the thioether in L(ESE), led to the formation of a bis(μ-oxo) species [{(L(EOE))Cu(III)}(2)(O(2-))(2)](2+) (3b(O); 380 nm, ε ∼ 10,000 M(-1) cm(-1)). This result provides further support for the sulfur influence in 1b(P) and 2b(P), in particular coordination of the sulfur to the Cu. Thermal decomposition of 1b(P) is accompanied by ligand sulfoxidation. The structure of [{(L(EOE))Cu(II)(Cl)}(2)](+) (3c) generated from the reductive dehalogenation of organic chlorides suggests that the ether moiety is weakly bound to the cupric ion. A detailed discussion of the spectroscopic and structural characteristics of 1b(P), 2b(P), and 3b(O) is presented.
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Affiliation(s)
- Yunho Lee
- Department of Chemistry, the Johns Hopkins University, Baltimore, Maryland 21218, USA
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15
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Toluene and ethylbenzene aliphatic C-H bond oxidations initiated by a dicopper(II)-mu-1,2-peroxo complex. J Am Chem Soc 2010; 131:3230-45. [PMID: 19216527 DOI: 10.1021/ja807081d] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
With an anisole-containing polypyridylamine potential tetradentate ligand (O)L, a mu-1,2-peroxo-dicopper(II) complex [{(O)LCu(II)}(2)(O(2)(2-))](2+) forms from the reaction of the mononuclear compound [Cu(I)((O)L)(MeCN)]B(C(6)F(5))(4) ((O)LCu(I)) with O(2) in noncoordinating solvents at -80 degrees C. Thermal decay of this peroxo complex in the presence of toluene or ethylbenzene leads to rarely seen C-H activation chemistry; benzaldehyde and acetophenone/1-phenylethanol mixtures, respectively, are formed. Experiments with (18)O(2) confirm that the oxygen source in the products is molecular O(2) and deuterium labeling experiments indicate k(H)/k(D) = 7.5 +/- 1 for the toluene oxygenation. The O(2)-reaction of [Cu(I)((Bz)L)(CH(3)CN)](+) ((Bz)LCu(I)) leads to a dicopper(III)-bis-mu-oxo species [{(Bz)LCu(III)}(2)(mu-O(2-))(2)](2+) at -80 degrees C, and from such solutions, very similar toluene oxygenation chemistry occurs. Ligand (Bz)L is a tridentate chelate, possessing the same moiety found in (O)L, but without the anisole O-atom donor. In these contexts, the nature of the oxidant species in or derived from [{(O)LCu(II)}(2)(O(2)(2-))](2+) is discussed and likely mechanisms of reaction initiated by toluene H-atom abstraction chemistry are detailed. To confirm the structural formulations of the dioxygen-adducts, UV-vis and resonance Raman spectroscopic studies have been carried out and these results are reported and compared to previously described systems including [{Cu(II)((Py)L)}(2)(O(2))](2+) ((Py)L = TMPA = tris(2-methylpyridyl)amine). Using (L)Cu(I), CO-binding properties (i.e., nu(C-O) values) along with electrochemical property comparisons, the relative donor abilities of (O)L, (Bz)L, and (Py)L are assessed.
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Sircoglou M, Bontemps S, Mercy M, Miqueu K, Ladeira S, Saffon N, Maron L, Bouhadir G, Bourissou D. Copper(I) complexes derived from mono- and diphosphino-boranes: Cu-->B interactions supported by arene coordination. Inorg Chem 2010; 49:3983-90. [PMID: 19891437 DOI: 10.1021/ic901896z] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The monophosphino-boranes o-iPr(2)P(C(6)H(4))BR(2) (1: R = Ph and 3: R = Cy) and diphosphino-boranes [o-R(2)P(C(6)H(4))](2)BPh (5: R = Ph and 6: R = iPr) readily react with CuCl to afford the corresponding complexes {[o-iPr(2)P(C(6)H(4))BPh(2)]Cu(mu-Cl)}(2) 2, {[o-iPr(2)P(C(6)H(4))BCy(2)]Cu(mu-Cl)}(2) 4, {[o-Ph(2)P(C(6)H(4))](2)BPh}CuCl 7, and {[o-iPr(2)P(C(6)H(4))](2)BPh}CuCl 8. The presence of Cu-->B interactions supported by arene coordination within complexes 2, 7, and 8 has been unambiguously evidenced by NMR spectroscopy and X-ray diffraction studies. The unique eta(2)-BC coordination mode adopted by complexes 7 and 8 has been thoroughly analyzed by density-functional theory (DFT) calculations.
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Affiliation(s)
- M Sircoglou
- Université de Toulouse, UPS, LHFA, 118 route de Narbonne, F-31062 Toulouse, France
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Lucas HR, Karlin KD. Copper-Carbon Bonds in Mechanistic and Structural Probing of Proteins as well as in Situations where Copper is a Catalytic or Receptor Site. METAL-CARBON BONDS IN ENZYMES AND COFACTORS 2009. [DOI: 10.1039/9781847559333-00295] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
While copper-carbon bonds are well appreciated in organometallic synthetic chemistry, such occurrences are less known in biological settings. By far, the greatest incidence of copper-carbon moieties is in bioinorganic research aimed at probing copper protein active site structure and mechanism; for example, carbon monoxide (CO) binding as a surrogate for O2. Using infrared (IR) spectroscopy, CO coordination to cuprous sites has proven to be an extremely useful tool for determining active site copper ligation (e.g., donor atom number and type). The coupled (hemocyanin, tyrosinase, catechol oxidase) and non-coupled (peptidylglycine α-hydroxylating monooxygenase, dopamine β-monooxygenase) binuclear copper proteins as well as the heme-copper oxidases (HCOs) have been studied extensively via this method. In addition, environmental changes within the vicinity of the active site have been determined based on shifts in the CO stretching frequencies, such as for copper amine oxidases, nitrite reductases and again in the binuclear proteins and HCOs. In many situations, spectroscopic monitoring has provided kinetic and thermodynamic data on CuI-CO formation and CO dissociation from copper(I); recently, processes occurring on a femtosecond timescale have been reported. Copper-cyano moieties have also been useful for obtaining insights into the active site structure and mechanisms of copper-zinc superoxide dismutase, azurin, nitrous oxide reductase, and multi-copper oxidases. Cyanide is a good ligand for both copper(I) and copper(II), therefore multiple physical-spectroscopic techniques can be applied. A more obvious occurrence of a “Cu-C” moiety was recently described for a CO dehydrogenase which contains a novel molybdenum-copper catalytic site. A bacterial copper chaperone (CusF) was recently established to have a novel d-π interaction comprised of copper(I) with the arene containing side-chain of a tryptophan amino acid residue. Meanwhile, good evidence exists that a plant receptor site (ETR1) utilizes copper(I) to sense ethylene, a growth hormone. A copper olfactory receptor has also been suggested. All of the above mentioned occurrences or uses of carbon-containing substrates and/or probes are reviewed and discussed within the framework of copper proteins and other relevant systems.
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Affiliation(s)
- Heather R. Lucas
- Department of Chemistry, The Johns Hopkins University 3400 N. Charles Street Baltimore MD 21218 USA
| | - Kenneth D. Karlin
- Department of Chemistry, The Johns Hopkins University 3400 N. Charles Street Baltimore MD 21218 USA
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Shimazaki Y, Takani M, Yamauchi O. Metal complexes of amino acids and amino acid side chain groups. Structures and properties. Dalton Trans 2009:7854-69. [PMID: 19771344 DOI: 10.1039/b905871k] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Mandal S, De A, Mukherjee R. Formation of {Cu2(III)(mu-O)2}2+ core due to dioxygen reactivity of a copper(I) complex supported by a new hybrid tridentate ligand: reaction with exogenous substrates. Chem Biodivers 2008; 5:1594-1608. [PMID: 18729094 DOI: 10.1002/cbdv.200890147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Reaction of a Cu(I) complex of a hybrid tridentate ligand, encompassing [2-(pyridin-2-yl)ethyl]amine and dimethyl-substituted ethylalkylamine with dioxygen, generates in acetone at -80 degrees putative bis(mu-oxo)dicopper(III) intermediate. Structural characterization of a PPh(3)-adduct of a mononuclear Cu(I) complex of this new ligand has been achieved. This ligand coordinates in a facial mode utilizing three N-atoms (-CH(2)CH(2)-Py, -CH(2)CH(2)NMe(2), and -NCH(2)Ph). Reactivity of bis(mu-oxo)dicopper(III) intermediate toward exogenous substrates (2,4-di(tert-butyl)phenol and 2,4,6-tri(tert-butyl)phenol) has also been investigated.
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Affiliation(s)
- Sukanta Mandal
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
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Cañon-Mancisidor W, Spodine E, Venegas-Yazigi D, Rojas D, Manzur J, Alvarez S. Electrochemical Behavior of Copper Complexes with Substituted Polypyridinic Ligands: An Experimental and Theoretical Study. Inorg Chem 2008; 47:3687-92. [PMID: 18366154 DOI: 10.1021/ic702104u] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | | | | | | | - Santiago Alvarez
- Departamento de Química Inorgànica i Centre de Recerca en Química Teòrica, Universitat de Barcelona, Barcelona, Spain
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Astner J, Weitzer M, Foxon SP, Schindler S, Heinemann FW, Mukherjee J, Gupta R, Mahadevan V, Mukherjee R. Syntheses, characterization, and reactivity of copper complexes with tridentate N-donor ligands. Inorganica Chim Acta 2008. [DOI: 10.1016/j.ica.2007.07.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Manzur J, Vega A, García AM, Acuña C, Sieger M, Sarkar B, Niemeyer M, Lissner F, Schleid T, Kaim W. Coordination Alternatives in Dinuclear Bis(pyridin-2-ylalkyl)benzylaminecopper(II) Complexes with OH–, RO–, F–, or Cl– Bridges: Experimental Structures and DFT Preferences. Eur J Inorg Chem 2007. [DOI: 10.1002/ejic.200700637] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Cramer CJ, Tolman WB. Mononuclear Cu-O2 complexes: geometries, spectroscopic properties, electronic structures, and reactivity. Acc Chem Res 2007; 40:601-8. [PMID: 17458929 PMCID: PMC2593863 DOI: 10.1021/ar700008c] [Citation(s) in RCA: 321] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Using interwoven experimental and theoretical methods, detailed studies of several structurally defined 1:1 Cu-O 2 complexes have provided important fundamental chemical information useful for understanding the nature of intermediates involved in aerobic oxidations in synthetic and enzymatic copper-mediated catalysis. In particular, these studies have shed new light on the factors that influence the mode of O 2 coordination (end-on vs side-on) and the electronic structure, which can vary between Cu(II)-superoxo and Cu(III)-peroxo extremes.
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Affiliation(s)
- Christopher J Cramer
- Department of Chemistry, Supercomputer Institute, and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant Street Southeast, Minneapolis, Minnesota 55410, USA.
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York JT, Llobet A, Cramer CJ, Tolman WB. Heterobimetallic dioxygen activation: synthesis and reactivity of mixed Cu-Pd and Cu-Pt bis(mu-oxo) complexes. J Am Chem Soc 2007; 129:7990-9. [PMID: 17550254 PMCID: PMC2625287 DOI: 10.1021/ja071744g] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Heterobimetallic CuPd and CuPt bis(mu-oxo) complexes have been prepared by the reaction of (PPh3)2MO2 (M=Pd, Pt) with LCu(I) precursors (L=beta-diketiminate and di- and triamine ligands) and characterized by low-temperature UV-vis, resonance Raman, and 1H and 31P[1H] NMR spectroscopy in conjunction with DFT calculations. The complexes decompose upon warming to yield OPPh3, and in one case this was shown to occur by an intramolecular process through crossover experiments using double-labeling (oxo and phosphine). The reactivity of one of the complexes, LMe2Cu(mu-O)2Pt(PPh3)2 (LMe2 = beta-diketiminate), with a variety of reagents including CO2, 2,4-di-tert-butylphenol, 2,4-di-tert-butylphenolate, [NH4][PF6], and dihydroanthracene, was compared to that of homometallic Pt2 and Cu2 counterparts. Unlike typical [Cu2(mu-O)2]2+ cores which have electrophilic oxo groups, the oxo groups in the [Cu(mu-O)2Pt]+ core behave as bases and nucleophiles, similar to previously described Pt2 compounds. In addition, however, the [Cu(mu-O)2Pt]+ core is capable of oxidatively coupling 2,4-di-tert-butylphenol and 2,4-di-tert-butylphenolate. Theoretical evaluation of the electron affinities, basicities, and H-atom transfer kinetics and thermodynamics of the Cu2 and CuM (M=Pd, Pt) cores showed that the latter are more basic and form stronger O-H bonds.
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Affiliation(s)
- John T York
- Department of Chemistry, Center for Metals in Biocatalysis, and Supercomputer Institute, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA
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Matsumoto T, Furutachi H, Nagatomo S, Tosha T, Fujinami S, Kitagawa T, Suzuki M. Synthesis and reactivity of (μ-η2:η2-peroxo)dicopper(II) complexes with dinucleating ligands: Hydroxylation of xylyl linker with a NIH shift. J Organomet Chem 2007. [DOI: 10.1016/j.jorganchem.2006.05.068] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kunishita A, Osako T, Tachi Y, Teraoka J, Itoh S. Syntheses, Structures, and O2-Reactivities of Copper(I) Complexes with Bis(2-pyridylmethyl)amine and Bis(2-quinolylmethyl)amine Tridentate Ligands. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2006. [DOI: 10.1246/bcsj.79.1729] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Zhao SB, Wang RY, Wang S. Dinuclear Cu(I) Complexes of 1,2,4,5-Tetra(7-azaindolyl)benzene: Persistent 3-Coordinate Geometry, Luminescence, and Reactivity. Inorg Chem 2006; 45:5830-40. [PMID: 16841988 DOI: 10.1021/ic060237h] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Five Cu(I) complexes [Cu2(ttab)(CH3CN)2][BF4]2 (1), [Cu(2)(ttab)(PPh3)2][BF4]2 (2), [Cu2(ttab)I2] (3), [Cu2(ttab)(I3)2] (4), and [Cu2(ttab)(I)BF4]n (5) with 1,2,4,5-tetra(7-azaindolyl)benzene (ttab) have been synthesized and characterized. The structures of compound 1, 2, 4, and 5 have been determined by single-crystal X-ray diffraction analyses, which established that 1, 2, and 4 are discrete dinuclear Cu2 compounds while compound 5 is a 1D coordination polymer with the I- ligand bridging two dinuclear Cu2 units. The ttab ligand in all four complexes adopts a 1,3-chelation mode. The Cu(I) center in all complexes is three-coordinate. Close contact between the Cu(I) center and the benzene ring in the ttab ligand was observed in all four structures, which is believed to play a role in stabilizing the three-coordinate geometry of the Cu(I) center. The crystals of 1, 2, and 5 contain channels in the lattice that host solvent molecules such as CH2Cl2 and toluene. Fluorescent measurements established that, in solution, compounds 1-3 display weak blue luminescence which originates from the ttab but is significantly red-shifted and has a much lower emission intensity, compared to the free ttab ligand. The application of compound 1 in C-N cross-coupling reactions was examined by using the reaction of phenyl halides with imidazole as a model system. For the reaction with phenyl iodide, 1 was found to be as effective a catalyst as the CuI/1,10-phenanthroline system. For the reaction with phenyl bromide, 1 is less effective than the CuI/1,10-phenanthroline system. Compound 1 reacts with O2 gas, as established by UV-vis spectra, but the oxidized products have not been characterized.
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Affiliation(s)
- Shu-Bin Zhao
- Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada
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Hill LMR, Gherman BF, Aboelella NW, Cramer CJ, Tolman WB. Electronic tuning of β-diketiminate ligands with fluorinated substituents: effects on the O2-reactivity of mononuclear Cu(i) complexes. Dalton Trans 2006:4944-53. [PMID: 17047744 DOI: 10.1039/b609939d] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Copper(i) complexes with the beta-diketiminate ligands HC{C(R)N(Dipp)}{C(R')N(Dipp)}(-) (Dipp = C(6)H(3)(i)Pr(2-)2,6; L(1), R = CF(3), R' = CH(3); L(2), R = R' = CF(3)) have been isolated and fully characterized. On the basis of X-ray structural comparisons with the previously reported complex LCu(CH(3)CN) (L = HC{C(CH(3))N(Dipp)}(2)(-)), the ligand environments at the copper centers in the analogous nitrile adducts with L(1) and L(2) impose similar steric demands. L(1)Cu(CH(3)CN) reacts instantaneously at low temperature with O(2) to form a thermally-unstable intermediate with an isotope-sensitive vibration at 977 cm(-1) (928 cm(-1) with (18)O(2)), in accord with the peroxo O-O stretch associated with side-on coordination for LCu(O(2)). However, L(2)Cu(CH(3)CN) is unreactive toward O(2) even at room temperature. Evaluation of the redox potentials of the nitrile adducts and the CO stretching frequencies of the carbon monoxide adducts revealed an incremental adjustment of the electronic environment at the copper center that correlated with the extent of ligand fluorination. Furthermore, theoretical calculations (DFT, CASPT2) predicted that an increasing extent of Cu(ii)-superoxo character and end-on coordination of the O(2) moiety in the Cu/O(2) product (L(2) > L(1) > L) are accompanied by increases in the free energy for the oxygenation reaction, with L(2) unable to support a Cu/O(2) intermediate. Calculations also predict the 1 : 1 Cu/O(2) adducts to be unreactive with respect to hydrogen atom abstraction from hydrocarbon substrates on the basis of their stability towards both reduction and protonation.
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Affiliation(s)
- Lyndal M R Hill
- Department of Chemistry, Center for Metals in Biocatalysis, and Supercomputer Institute, University of Minnesota, 207 Pleasant St. SE, Minneapolis, 55455-0431, USA
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Itoh S, Tachi Y. Structure and O2-reactivity of copper(i) complexes supported by pyridylalkylamine ligands. Dalton Trans 2006:4531-8. [PMID: 17016563 DOI: 10.1039/b607964d] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structure and O2-reactivity of a series of copper(I) complexes supported by the pyridylalkylamine ligands are summarized, and the ligand effects such as the chelate ring size effect (five- vs. six-membered ring), the denticity effect (tetradentate vs. tridentate vs. didentate), the steric effect of 6-methylpyridine and the steric and/or electronic effects of N-alkyl substituents are discussed in detail.
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Affiliation(s)
- Shinobu Itoh
- Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Osaka, 558-8585, Japan.
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Garner D, McMaster J, Raven E, Walton P. Dalton Discussion No. 8. Metals: centres of biological activity. Dalton Trans 2005:3372-4. [PMID: 16234913 DOI: 10.1039/b513314a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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