1
|
Sharma A, Mejia K, Ueno H, Zhou W, Chiang L. Copper complexes of strongly electron rich and deficient salen ligands. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2022.121106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
2
|
Xue X, Fu Y, He L, Salassa L, He LF, Hao YY, Koh MJ, Soulié C, Needham RJ, Habtemariam A, Garino C, Lomachenko KA, Su Z, Qian Y, Paterson MJ, Mao ZW, Liu HK, Sadler PJ. Photoactivated Osmium Arene Anticancer Complexes. Inorg Chem 2021; 60:17450-17461. [PMID: 34503331 DOI: 10.1021/acs.inorgchem.1c00241] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Half-sandwich Os-arene complexes exhibit promising anticancer activity, but their photochemistry has hardly been explored. To exploit the photocytotoxicity and photochemistry of Os-arenes, O,O-chelated complexes [Os(η6-p-cymene)(Curc)Cl] (OsCUR-1, Curc = curcumin) and [Os(η6-biphenyl)(Curc)Cl] (OsCUR-2), and N,N-chelated complexes [Os(η6-biphenyl)(dpq)I]PF6 (OsDPQ-2, dpq = pyrazino[2,3-f][1,10]phenanthroline) and [Os(η6-biphenyl)(bpy)I]PF6 (OsBPY-2, bpy = 2,2'-bipyridine), have been investigated. The Os-arene curcumin complexes showed remarkable photocytotoxicity toward a range of cancer cell lines (blue light IC50: 2.6-5.8 μM, photocytotoxicity index PI = 23-34), especially toward cisplatin-resistant cancer cells, but were nontoxic to normal cells. They localized mainly in mitochondria in the dark but translocated to the nucleus upon photoirradiation, generating DNA and mitochondrial damage, which might contribute toward overcoming cisplatin resistance. Mitochondrial damage, apoptosis, ROS generation, DNA damage, angiogenesis inhibition, and colony formation were observed when A549 lung cancer cells were treated with OsCUR-2. The photochemistry of these Os-arene complexes was investigated by a combination of NMR, HPLC-MS, high energy resolution fluorescence detected (HERFD), X-ray adsorption near edge structure (XANES) spectroscopy, total fluorescence yield (TFY) XANES spectra, and theoretical computation. Selective photodissociation of the arene ligand and oxidation of Os(II) to Os(III) occurred under blue light or UVA excitation. This new approach to the design of novel Os-arene complexes as phototherapeutic agents suggests that the novel curcumin complex OsCUR-2, in particular, is a potential candidate for further development as a photosensitizer for anticancer photoactivated chemotherapy (PACT).
Collapse
Affiliation(s)
- Xuling Xue
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Ying Fu
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.,National Center for Advancing Translational Sciences (NCATS/NIH), Rockville, Maryland 20850, United States
| | - Liang He
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China
| | - Luca Salassa
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, Donostia 20018, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao 48011, Spain.,Kimika Fakultatea, Euskal Herriko Unibertsitatea, UPV/EHU, Donostia 20080, Spain
| | - Ling-Feng He
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Science, Nanjing Normal University, Nanjing 210023, China
| | - Yuan-Yuan Hao
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Madeleine J Koh
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Clément Soulié
- Institute of Chemical Sciences, School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, Scotland EH14 4AS, U.K
| | - Russell J Needham
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | | | - Claudio Garino
- Department of Chemistry and NIS Interdepartmental Center, University of Turin, Turin I-10135, Italy
| | - Kirill A Lomachenko
- Department of Chemistry and NIS Interdepartmental Center, University of Turin, Turin I-10135, Italy.,European Synchrotron Radiation Facility, 71 avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France.,The Smart Materials Research Institute, Southern Federal University, Rostov-on-Don 344090, Russia
| | - Zhi Su
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Yong Qian
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Martin J Paterson
- Institute of Chemical Sciences, School of Engineering & Physical Sciences, Heriot-Watt University, Edinburgh, Scotland EH14 4AS, U.K
| | - Zong-Wan Mao
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China
| | - Hong-Ke Liu
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Peter J Sadler
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| |
Collapse
|
3
|
Chatterjee M, Mondal S, Hazari AS, Záliš S, Kaim W, Lahiri GK. Variable electronic structure and spin distribution in bis(2,2'-bipyridine)-metal complexes (M = Ru or Os) of 4,5-dioxido- and 4,5-diimido-pyrene. Dalton Trans 2021; 50:4191-4201. [PMID: 33683255 DOI: 10.1039/d1dt00282a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The odd-electron compounds [M(bpy)2(L1)](ClO4) M = Ru ([1](ClO4)) or Os ([2](ClO4)), and the even-electron species [M(bpy)2(H2L2)](ClO4)2, M = Ru ([3](ClO4)2) or Os ([4](ClO4)2) were obtained from pyrene-4,5-dione, L1, or 4,5-diaminopyrene, H4L2, and were characterised structurally, electrochemically and spectroscopically. Experimental and computational analysis (TD-DFT) revealed rather different electronic structures and spin distributions of the paramagnetic monocations 1+-4+. EPR investigations and electronic absorption studies exhibit increasing metal contributions to the singly occupied MO along the series 1+ < 3+ < 4+ < 2+, illustrated by g value and long-wavelength absorbance. In addition to variations of the metal (Ru,Os) and the donor atoms (O,NH) the extension of the π system of the semiquinone-type ligand has a large effect on the electronic structure of the paramagnetic cations.
Collapse
Affiliation(s)
- Madhumita Chatterjee
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
| | | | | | | | | | | |
Collapse
|
4
|
Gianino J, Brown SN. Highly covalent metal-ligand π bonding in chelated bis- and tris(iminoxolene) complexes of osmium and ruthenium. Dalton Trans 2020; 49:7015-7027. [PMID: 32367103 DOI: 10.1039/d0dt01287d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The bis(aminophenol) 2,2'-biphenylbis(3,5-di-tert-butyl-2-hydroxyphenylamine) (ClipH4) forms trans-(Clip)Os(py)2 upon aerobic reaction of the ligand with {(p-cymene)OsCl2}2 in the presence of pyridine and triethylamine. A more oxidized species, cis-β-(Clip)Os(OCH2CH2O), is formed from reaction of the ligand with the osmium(vi) complex OsO(OCH2CH2O)2, and reacts with Me3SiCl to give the chloro complex cis-β-(Clip)OsCl2. Octahedral osmium and ruthenium tris-iminoxolene complexes are formed from the chelating ligand tris(2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)amino-4-methylphenyl)amine (MeClampH6) on aerobic reaction with divalent metal precursors. The complexes' structural and electronic features are well described using a simple bonding model that emphasizes the covalency of the π bonding between the metal and iminoxolene ligands rather than attempting to dissect the parts into discrete oxidation states. Emphasizing the continuity of bonding between disparate complexes, the structural data from a variety of Os and Ru complexes show good correlations to π bond order, and the response of the intraligand bond distances to the bond order can be analyzed to illuminate the polarity of the bonding between metal and the redox-active orbital on the iminoxolenes. The osmium compounds'π bonding orbitals are about 40% metal-centered and 60% ligand-centered, with the ruthenium compounds' orbitals about 65% metal-centered and 35% ligand-centered.
Collapse
Affiliation(s)
- Jacqueline Gianino
- Department of Chemistry and Biochemistry, 251 Nieuwland Science Hall, University of Notre Dame, Notre Dame, IN 46556-5670, USA.
| | | |
Collapse
|
5
|
Rajput A, Sharma AK, Barman SK, Lloret F, Mukherjee R. Six-coordinate [Co III(L) 2] z (z = 1-, 0, 1+) complexes of an azo-appended o-aminophenolate in amidate(2-) and iminosemiquinonate π-radical (1-) redox-levels: the existence of valence-tautomerism. Dalton Trans 2018; 47:17086-17101. [PMID: 30465680 DOI: 10.1039/c8dt03257b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Aerobic reaction of the ligand H2L1, 2-(2-phenylazo)-anilino-4,6-di-tert-butylphenol, CoCl2·6H2O and Et3N in MeOH under refluxing conditions produces, after work-up and recrystallization, black crystals of [Co(L1)2] (1). When examined by cyclic voltammetry, 1 displays in CH2Cl2 three one-electron redox responses: two oxidative, E11/2 = 0.30 V (peak-to-peak separation, ΔEp = 100 mV) and E21/2 = 1.04 V (ΔEp = 120 mV), and one reductive E1/2 = -0.27 V (ΔEp = 120 mV) vs. SCE. Consequently, 1 is chemically oxidized by 1 equiv. of [FeIII(η5-C5H5)2][PF6], affording the isolation of deep purple crystals of [Co(L1)2][PF6]·2CH2Cl2 (2), and one-electron reduction with [CoII(η5-C5H5)2] yielded bluish-black crystals of [CoIII(η5-C5H5)2][Co(L1)2]·MeCN (3). A solid sample of 1 exhibits temperature-independent (50-300 K) magnetism, revealing the presence of a free radical (S = 1/2), which exhibits an isotropic EPR signal (g = 2.003) at 298 K and at 77 K an eight-line feature characteristic of hyperfine-interaction of the radical with the Co (I = 7/2) nucleus. Based on X-ray structural parameters of 1-3 at 100 K, magnetic and EPR spectral behaviour of 1, and variable-temperature (233-313 K) 1H NMR spectral features of 1-3 and 13C NMR spectra at 298 K of 2 and 3 in CDCl3 point to the electronic structure of the complexes as either [CoIII{(LAP)2-}{(LISQ)}˙-] or [CoIII{(L1)2}˙3-] (delocalized nature favours the latter description) (1), [CoIII{(LISQ)˙-}2][PF6]·2CH2Cl2 (2) and [CoIII(η5-C5H5)2][CoIII{(LAP)2-}2]·MeCN (3) [(LAP)2- and (LISQ)˙- represent the redox-level of coordinated ligands o-amidophenolate(2-) ion and o-iminobenzosemiquinonate(1-) π-radical ion, respectively]. Notably, all the observed redox processes are ligand-centred. To the best of our knowledge, this is the first time that six-coordinate complexes of a common tridentate o-aminophenolate-based ligand have been structurally characterized for the parent 1, its monocation 2 and the monoanion 3 counterparts. Temperature-dependent 1H NMR spectra reveal the existence of valence-tautomeric equilibria in 1-3. Density Functional Theory (DFT) calculations at the B3LYP-level of theory corroborate the electronic structural assignment of 1-3 from experimental data. The origins of the observed UV-VIS-NIR absorptions for 1-3 have been assigned, based on time-dependent (TD)-DFT calculations.
Collapse
Affiliation(s)
- Amit Rajput
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India.
| | | | | | | | | |
Collapse
|
6
|
Sarkar P, Mondal MK, Sarmah A, Maity S, Mukherjee C. An Iminosemiquinone-Coordinated Oxidovanadium(V) Complex: A Combined Experimental and Computational Study. Inorg Chem 2017; 56:8068-8077. [DOI: 10.1021/acs.inorgchem.7b00789] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Prasenjit Sarkar
- Department of Chemistry, Indian Institute of Technology Guwahati (IITG), Guwahati 781039, Assam, India
| | - Manas Kumar Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati (IITG), Guwahati 781039, Assam, India
| | - Amrit Sarmah
- Department
of Molecular Modelling, Institute of Organic Chemistry and Biochemistry ASCR, Flemingovo nám. 2, CZ-16610 Prague 6, Czech Republic
| | - Suvendu Maity
- Department
of Chemistry, R. K. Mission Residential College, Narendrapur, Kolkata 700103, India
| | - Chandan Mukherjee
- Department of Chemistry, Indian Institute of Technology Guwahati (IITG), Guwahati 781039, Assam, India
| |
Collapse
|
7
|
Das A, Ghosh P, Priego JL, Jiménez-Aparicio R, Lahiri GK. Unsymmetric (μ-oxido)/(μ-pyrazolato) and Symmetric (μ-pyrazolato)2 Bridged Diosmium Frameworks: Electronic Structure and Magnetic Properties. Inorg Chem 2016; 55:8396-406. [DOI: 10.1021/acs.inorgchem.6b00898] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Prabir Ghosh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - José Luis Priego
- Departamento de Química Inorgánica, Facultad
de Ciencias Químicas, Universidad Complutense, Ciudad Universitaria, E-28040 Madrid, Spain
| | - Reyes Jiménez-Aparicio
- Departamento de Química Inorgánica, Facultad
de Ciencias Químicas, Universidad Complutense, Ciudad Universitaria, E-28040 Madrid, Spain
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| |
Collapse
|
8
|
Ali A, Dhar D, Barman SK, Lloret F, Mukherjee R. Nickel(II) Complex of a Hexadentate Ligand with Two o-Iminosemiquinonato(1-) π-Radical Units and Its Monocation and Dication. Inorg Chem 2016; 55:5759-71. [PMID: 27232547 DOI: 10.1021/acs.inorgchem.5b02688] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Aerobic reaction of a hexadentate redox-active o-aminophenol-based ligand, H4L(3) = N,N'-bis(2-hydroxy-3,5-di-tert-butylphenyl)-2,2'-diamino(diphenyldithio)-ethane, in CH3OH with Ni(II)(O2CCH3)2·4H2O and Et3N afforded isolation of a reddish-brown crystalline solid [Ni(L(3))] 1. Cyclic voltammetry (CV) experiment exhibits two oxidative responses at E1/2 = 0.09 and 0.53 V vs SCE (saturated calomel electrode). Chemical oxidation of 1 in air by [Fe(III)(η(5)-C5H5)2][PF6] and AgBF4 in CH2Cl2 led to the isolation of one-electron oxidized species [1](1+) as purple [1][PF6]·CH2Cl2 and two-electron oxidized species [1](2+) as dark purple [1][BF4]2·CH2Cl2, respectively. X-ray crystallographic analysis at 100(2) K unambiguously established that the ligand is present in [Ni(II){(L(ISQ)O,N)(•-)}{(L(ISQ)O,N)(•-)}{(LS,S)(0)}] 1, [Ni(II){(L(IBQ)O,N)(0)}{(L(ISQ)O,N)(•-)}{(LS,S)(0)}][PF6]·CH2Cl2, and [Ni(II){(L(IBQ)O,N)(0)}{(L(IBQ)O,N)(0)}{(LS,S)(0)}][BF4]2·CH2Cl2, as monoanionic o-iminosemiquinonate(1-) π-radical (Srad = 1/2) (L(ISQ))(•-) and neutral o-iminoquinone (L(IBQ))(0) redox-levels. Complexes 1, [1][PF6]·CH2Cl2, and [1][BF4]2·CH2Cl2 possess an S = 2, 3/2, and 1 ground-state, respectively, established by temperature-dependent (2-300 K) magnetic behavior of 1 and [1][PF6]·CH2Cl2, and a μeff value of [1][BF4]2·CH2Cl2 at 300 K. Both 1 and [1][PF6]·CH2Cl2 exhibit ferromagnetic exchange-coupling between the two electrons of Ni(II) and two/one ligand π-radicals, respectively. The redox processes are shown to be ligand-based. Spectroscopic and redox properties, and density functional theory (DFT) calculations at the CAM-B3LYP-level of theory adequately describe the electronic structure of 1, [1](1+), and [1](2+). The observed UV-vis-NIR absorptions for 1, [1][PF6]·CH2Cl2, and [1][BF4]2·CH2Cl2 have been assigned, based on time-dependent (TD)-DFT calculations.
Collapse
Affiliation(s)
- Akram Ali
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, India
| | - Debanjan Dhar
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, India
| | - Suman K Barman
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, India.,Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata , Mohanpur 741 246, India
| | - Francesc Lloret
- Departament de Quımíca, Inorgànica/Instituto de Ciencia Molecular (ICMOL), Universitat de Valeńcia , Polígono de la Coma, s/n, 46980-Paterna, València, Spain
| | - Rabindranath Mukherjee
- Department of Chemistry, Indian Institute of Technology Kanpur , Kanpur 208 016, India.,Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata , Mohanpur 741 246, India
| |
Collapse
|
9
|
Ghorai S, Sarmah A, Roy RK, Tiwari A, Mukherjee C. Effect of Geometrical Distortion on the Electronic Structure: Synthesis and Characterization of Monoradical-Coordinated Mononuclear Cu(II) Complexes. Inorg Chem 2016; 55:1370-80. [PMID: 26812584 DOI: 10.1021/acs.inorgchem.5b01257] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ligand H3Sami(Mixed(tBu)) was composed of two different compartments, a redox-active 2-aminophenol and a salen salicylidene. Both compartments were linked via a benzyl linker. The ligand reacted with CuCl2·2H2O under air in the presence of Et3N and provided the corresponding monoradical-coordinated mononuclear Cu(II) complex (1). Complex 1, in solution, reacted with air and provided complex 2 via ligand-centered oxygenation at the benzyl-CH2 position. Both complexes were characterized via IR, mass spectrometry, X-ray single-crystal diffraction, variable-temperature magnetic susceptibility, cyclic voltammograms (CVs), and UV-vis/NIR spectroscopic techniques. X-ray crystallographic analyses clearly showed almost equally distorted square planar geometry around the Cu(II) atom in both complexes. However, the bending of the radical-containing C6 ring compared to the N1-Cu1-O1 plane was different in both complexes. While complex 1 was paramagnetic and showed a ferromagnetic coupling between the d(x(2)-y(2)) magnetic orbital of Cu(II) ion and the p(z) orbital of coordinated π-radical, complex 2 was diamagnetic by experiencing a strong antiferromagnetic coupling between the two magnetic orbitals. UV-vis/NIR spectra of the complexes were dominated by charge-transfer transitions. CVs of the complexes showed two reversible one-electron oxidations and one reversible one-electron reduction. E(1/2)(ox2) and E(1/2)(red1) potentials were different in both complexes, while E(1/2)(ox1) values were almost the same and the process corresponded to the formation of phenoxyl radical. Theoretical studies were also performed to understand the magnetic coupling phenomena, and TD-DFT calculations were employed for the assignment of charge-transfer absorption bands.
Collapse
Affiliation(s)
- Samir Ghorai
- Department of Chemistry, Indian Institute of Technology Guwahati , Guwahati, 781039 Assam, India
| | - Amrit Sarmah
- Department of Chemistry, Birla Institute of Technology and Science (BITS) , Pilani, 333031 Rajasthan, India
| | - Ram Kinkar Roy
- Department of Chemistry, Birla Institute of Technology and Science (BITS) , Pilani, 333031 Rajasthan, India
| | - Archana Tiwari
- Department of Physics, School of Physical Sciences, Sikkim University , Gangtok 737102 Sikkim, India
| | - Chandan Mukherjee
- Department of Chemistry, Indian Institute of Technology Guwahati , Guwahati, 781039 Assam, India
| |
Collapse
|
10
|
Das A, Mondal P, Dasgupta M, Kishore N, Lahiri GK. Substituent directed selectivity in anion recognition by a new class of simple osmium-pyrazole derived receptors. Dalton Trans 2016; 45:2605-17. [PMID: 26733437 DOI: 10.1039/c5dt04538j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The present article deals with the structurally, spectroscopically and electrochemically characterised osmium-bipyridyl derived complexes [(bpy)2Os(II)(HL1)Cl]ClO4 [1]ClO4 and [(bpy)2Os(II)(HL2)Cl]ClO4 [2]ClO4 incorporating neutral and monodentate pyrazole derivatives (HL) with one free NH function (bpy = 2,2'-bipyridine, HL1 = pyrazole, HL2 = 3,5-dimethylpyrazole). The crystal structures of [1]ClO4 and [2]ClO4 reveal intramolecular hydrogen bonding interactions between the free NH proton of HL and the equatorially placed Cl(-) ligand (N-HCl) with donor-acceptor distances of 3.114(7) Å and 3.153(6) Å as well as intermolecular hydrogen bonding interactions between the NH proton and one of the oxygen atoms of ClO4(-) (N-HO) with donor-acceptor distances of 2.870(10) Å and 3.024(8) Å, respectively. The effect of hydrogen bonding interactions has translated into the less acidic nature of the NH proton of the coordinated HL with estimated pKa > 12. 1(+) and 2(+) exhibit reversible Os(II)/(III) and irreversible Os(III)/(IV) processes in CH3CN within ± 2.0 V versus SCE. The effect of 3,5-dimethyl substituted HL2 on 2(+) has been reflected in the appreciable lowering (40 mV) of the Os(II/III) potential, along with the further decrease in the acidity of the NH proton (pKa > 13.0) with regard to HL1 coordinated 1(+) (pKa: ∼ 12.3). The electronic spectral features of Os(ii) (1(+)/2(+)) and electrochemically generated Os(III) (1(2+)/2(2+)) derived complexes have been analysed by TD-DFT calculations. The efficacy of the 1(+) and 2(+) encompassing free NH proton towards the anion recognition process has been evaluated by different experimental investigations using a wide variety of anions. It however establishes that receptor 1(+) can recognise both F(-) and OAc(-) in acetonitrile solution, while 2(+) is exclusively selective for the F(-) ion.
Collapse
Affiliation(s)
- Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
| | | | | | | | | |
Collapse
|
11
|
Mandal A, Schwederski B, Fiedler J, Kaim W, Lahiri GK. Evidence for Bidirectional Noninnocent Behavior of a Formazanate Ligand in Ruthenium Complexes. Inorg Chem 2015; 54:8126-35. [DOI: 10.1021/acs.inorgchem.5b01408] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Abhishek Mandal
- Department
of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| | - Brigitte Schwederski
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - Jan Fiedler
- J. Heyrovský Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova
3, CZ-18223 Prague, Czech Republic
| | - Wolfgang Kaim
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - Goutam Kumar Lahiri
- Department
of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| |
Collapse
|
12
|
Chiang L, Herasymchuk K, Thomas F, Storr T. Influence of Electron-Withdrawing Substituents on the Electronic Structure of Oxidized Ni and Cu Salen Complexes. Inorg Chem 2015; 54:5970-80. [DOI: 10.1021/acs.inorgchem.5b00783] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Linus Chiang
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Khrystyna Herasymchuk
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Fabrice Thomas
- Département de Chimie Moléculaire,
Chimie Inorganique Redox (CIRE), UMR-5250, Université Grenoble Alpes, BP 53, 38041 Grenoble
Cedex 9, France
| | - Tim Storr
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| |
Collapse
|
13
|
Ali A, Barman SK, Mukherjee R. Palladium(II) Complex of a Redox-Active Amidophenolate-Based O,N,S,N Ligand: Its Monocation and Dication and Reactivity with PPh3. Inorg Chem 2015; 54:5182-94. [DOI: 10.1021/ic503103e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Akram Ali
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
| | - Suman K. Barman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
- Department of Chemistry, Indian Institute of Science Education and Research Kolkata, Mohanpur 741 246, India
| | - Rabindranath Mukherjee
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208 016, India
- Department of Chemistry, Indian Institute of Science Education and Research Kolkata, Mohanpur 741 246, India
| |
Collapse
|
14
|
Das A, Mobin SM, Lahiri GK. Recognition of fractional non-innocent feature of osmium coordinated 2,2′-biimidazole or 2,2′-bis(4,5-dimethylimidazole) and their interactions with anions. Dalton Trans 2015; 44:13204-19. [DOI: 10.1039/c5dt01763g] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The non-innocent feature of osmium coordinated doubly deprotonated 2,2′-biimidazole derivatives in symmetric dimeric complexes leads to a mixed electronic structural configuration.
Collapse
Affiliation(s)
- Ankita Das
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| | - Shaikh M. Mobin
- Discipline of Chemistry
- School of Basic Sciences
- Indian Institute of Technology Indore
- Indore 452017
- India
| | - Goutam Kumar Lahiri
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| |
Collapse
|
15
|
Das D, Agarwala H, Chowdhury AD, Patra T, Mobin SM, Sarkar B, Kaim W, Lahiri GK. Four-Center Oxidation State Combinations and Near-Infrared Absorption in [Ru(pap)(Q)2]n(Q=3,5-Di-tert-butyl-N-aryl-1,2-benzoquinonemonoimine, pap=2-Phenylazopyridine). Chemistry 2013; 19:7384-94. [DOI: 10.1002/chem.201204620] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Indexed: 12/26/2022]
Affiliation(s)
- Dipanwita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Kundu S, Maity S, Maity AN, Ke SC, Ghosh P. Stabilization of oxidovanadium(iv) by organic radicals. Dalton Trans 2013; 42:4586-601. [DOI: 10.1039/c2dt32693k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|