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Synthesis, characterization, ab initio quantum chemical calculations and molecular docking studies of Se bearing phenoxo-bridged bimetallic Ni(II) complexes. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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2
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Park K, Padmanaban S, Kim S, Jung K, Yoon S. NNN Pincer‐functionalized Porous Organic Polymer Supported Ru(III) as a Heterogeneous Catalyst for Levulinic Acid Hydrogenation to γ‐Valerolactone. ChemCatChem 2020. [DOI: 10.1002/cctc.202001376] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Kwangho Park
- Clean Energy Research Centre Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul (Republic of Korea
| | - Sudakar Padmanaban
- Department of Chemistry Seoul National University 1 Gwanak-ro Gwanak-gu Seoul (Republic of Korea
| | - Seong‐Hoon Kim
- Department of Chemistry Chung Ang University 84 Heukseok-ro Dongjak-gu Seoul (Republic of Korea
| | - Kwang‐Deog Jung
- Clean Energy Research Centre Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul (Republic of Korea
| | - Sungho Yoon
- Department of Chemistry Chung Ang University 84 Heukseok-ro Dongjak-gu Seoul (Republic of Korea
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3
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Anjana SS, Varghese B, Murthy NN. Coligand modulated oxidative O-demethylation of a methyl ether appended tetradentate N-ligand in Co(ii) complexes. Dalton Trans 2020; 49:3187-3197. [PMID: 31967148 DOI: 10.1039/c9dt04609g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Two Co(ii) complexes of the formula CoLOMeX2 (X = Cl- (1a); X = I- (1b)), where LOMe is 2-methoxy-N,N-bis(pyridin-2-ylmethyl) aniline, were synthesized and their structure, spectra and reactivity were studied. Upon oxidation of 1a and 1b, the ligand LOMe undergoes demethylation at the metal centre resulting in the formation of Co(iii) complexes with modified phenoxide ligands. This is the very first example of oxidative O-demethylation reported at a Co(ii) centre. The oxidative behaviour exhibits a striking dependence on the nature of coligands coordinated to the metal centre. The Co(ii) complex 1a with stronger chloro coligands requires a strong oxidising agent like t-BuOOH for oxidative demethylation and the subsequent formation of a mononuclear Co(iii) complex with a demethylated ligand, CoLO-Cl2 (2). On the other hand, complex 1b with weaker iodo coligands undergoes oxidation in the presence of the weak oxidant O2 to form a dihydroxo bridged binuclear Co(iii) complex [Co2(LO-)2(OH)2]2+ (3) with modified phenoxide ligands. The oxidation of 1b to 3 is monitored and the intermediate Co(ii) iodo aqua complex [CoLOMeI(H2O)]+ and Co(ii) diaqua complex [CoLOMe(H2O)2]2+ are isolated and characterised.
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Affiliation(s)
- S S Anjana
- Department of Chemistry, IIT Madras, Chennai 600 036, India.
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4
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Ratnam A, Kumari S, Kumar R, Singh U, Ghosh K. Selective oxidation of benzyl alcohol catalyzed by ruthenium (III) complexes derived from tridentate mer-ligands having phenolato donor. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2019.120986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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5
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Haiduc I. Review. Inverse coordination. Organic nitrogen heterocycles as coordination centers. A survey of molecular topologies and systematization. Part 2. Six-membered rings. J COORD CHEM 2019. [DOI: 10.1080/00958972.2019.1670349] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Ionel Haiduc
- Facultatea de Chimie, Universitatea Babeş-Bolyai, Cluj-Napoca, Romania
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6
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Ghosh P, Dey S, Panda S, Lahiri GK. Solvent-Mediated Functionalization of Benzofuroxan on Electron-Rich Ruthenium Complex Platform. Chem Asian J 2018; 13:1582-1593. [DOI: 10.1002/asia.201800308] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 03/29/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Prabir Ghosh
- Department of Chemistry; Indian Institute of Technology Bombay; Powai Mumbai 400076 India
| | - Sanchaita Dey
- Department of Chemistry; Indian Institute of Technology Bombay; Powai Mumbai 400076 India
| | - Sanjib Panda
- Department of Chemistry; Indian Institute of Technology Bombay; Powai Mumbai 400076 India
| | - Goutam Kumar Lahiri
- Department of Chemistry; Indian Institute of Technology Bombay; Powai Mumbai 400076 India
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7
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Tseng TW, Mendiratta S, Luo TT, Chen TW, Lee YP. A new route to constructing rhenium(I)-based 8-hydroxyquinolate complexes: Synthesis, structures and luminescent properties. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.02.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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8
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More hydra than Janus – Non-classical coordination modes in complexes of oligopyridine ligands. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2017.06.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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9
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Ghosh P, Panda S, Banerjee S, Lahiri GK. Ruthenium-Hydride Mediated Unsymmetrical Cleavage of Benzofuroxan to 2-Nitroanilido with Varying Coordination Mode. Inorg Chem 2017; 56:10735-10747. [DOI: 10.1021/acs.inorgchem.7b01696] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Prabir Ghosh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Sanjib Panda
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Soumyodip Banerjee
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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10
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Singha Hazari A, Mandal A, Beyer K, Paretzki A, Kaim W, Lahiri GK. Metal–Metal Bridging Using the DPPP Dye System: Electronic Configurations within Multiple Redox Series. Inorg Chem 2017; 56:2992-3004. [DOI: 10.1021/acs.inorgchem.6b03112] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Arijit Singha Hazari
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Abhishek Mandal
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Katharina Beyer
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - Alexa Paretzki
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - 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
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11
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Ghosh P, Banerjee S, Lahiri GK. Ruthenium Derivatives of in Situ Generated Redox-Active 1,2-Dinitrosobenzene and 2-Nitrosoanilido. Diverse Structural and Electronic Forms. Inorg Chem 2016; 55:12832-12843. [DOI: 10.1021/acs.inorgchem.6b02197] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Prabir Ghosh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Soumyodip Banerjee
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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12
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Ansari MA, Mandal A, Paretzki A, Beyer K, Kaim W, Lahiri GK. Isomeric Diruthenium Complexes of a Heterocyclic and Quinonoid Bridging Ligand: Valence and Spin Alternatives for the Metal/Ligand/Metal Arrangement. Inorg Chem 2016; 55:12357-12365. [DOI: 10.1021/acs.inorgchem.6b02245] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mohd. Asif Ansari
- Department
of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Abhishek Mandal
- Department
of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Alexa Paretzki
- Institut für
Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring
55, Stuttgart D-70550, Germany
| | - Katharina Beyer
- Institut für
Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring
55, Stuttgart D-70550, Germany
| | - Wolfgang Kaim
- Institut für
Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring
55, Stuttgart D-70550, Germany
| | - Goutam Kumar Lahiri
- Department
of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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13
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Ghosh P, Lahiri GK. Impact of {Os(pap)2} in fine-tuning the binding modes and non-innocent potential of deprotonated 2,2'-bipyridine-3,3'-diol. Dalton Trans 2016; 45:5240-52. [PMID: 26893242 DOI: 10.1039/c6dt00013d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of ctc-Os(II)(pap)2Cl2 (pap = 2-phenylazopyridine, ctc = cis-trans-cis with respect to chlorides and pyridine/azo nitrogens of pap, respectively) and ambidentate 2,2'-bipyridine-3,3'-diol (H2L) leads to the simultaneous formation of isomeric [Os(II)(pap)2(HL(-))](+) ((2+)/(3+)), seven-membered chelate containing Os(II)(pap)2(L(2-)) (4) and diastereomeric [{Os(II)(pap)2}2(μ-L(2-))](2+) (5a(2+) (meso, ΔΛ)/5b(2+) (rac, ΔΔ/ΛΛ)). The reaction of 2,2'-biphenol (H2L') and ctc-Os(II)(pap)2Cl2 yields Os(II)(pap)2(L'(2-)) (6), an analogue of 4. The identities of the newly designed complexes have been established by different analytical, spectroscopic and X-ray diffraction techniques. (1)H-NMR spectra of the complexes and single crystal X-ray structures of selective derivatives [2]ClO4, [3]ClO4, [5a](ClO4)2, and 6 establish the retention of the tc-configuration of the precursor {Os(pap)2}. In isomeric 2(+) and 3(+), monodeprotonated HL(-) is linked to the {Os(II)(pap)2} fragment through N,N and N,O(-) donors, resulting in nearly planar five- and six-membered chelates with O-HO(-) and O-HN hydrogen bonds at its back face, respectively. The O(-),O(-) donating L'(2-) extends a severely twisted seven-membered chelate with the {Os(pap)2} unit in 6. The N,O(-)/O(-),N donors of deprotonated L(2-) bridge the two {Os(II)(pap)2} units in a symmetric fashion in 5a(2+), forming two moderately twisted six-membered chelates. Though the deprotonation of the O-HN hydrogen bond in (+) by another unit of {Os(II)(pap)2} generates a diastereomeric mixture of 5a(2+) and 5b(2+), attempts to deprotonate the relatively stronger O-H···O(-) hydrogen bond in 2(+) have failed. The isomeric 2(+)/3(+), seven-membered chelate containing 4/6 and diastereomeric 5a(2+)/5b(2+) exhibit distinctive (1)H-NMR and absorption spectra as well as electrochemical responses. The pap (N[double bond, length as m-dash]N) based two successive reductions and the participation of HL(-), L(2-), L'(2-) in the oxidation processes of the respective complexes have been revealed using EPR and DFT calculated MOs and Mulliken spin density plots at the intermediate paramagnetic states.
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Affiliation(s)
- Prabir Ghosh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
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14
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Mondal P, Chatterjee M, Paretzki A, Beyer K, Kaim W, Lahiri GK. Noninnocence of Indigo: Dehydroindigo Anions as Bridging Electron-Donor Ligands in Diruthenium Complexes. Inorg Chem 2016; 55:3105-16. [DOI: 10.1021/acs.inorgchem.6b00038] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Prasenjit Mondal
- Department
of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Madhumita Chatterjee
- Department
of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Alexa Paretzki
- Institut für
Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring
55, D-70550 Stuttgart, Germany
| | - Katharina Beyer
- Institut für
Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring
55, D-70550 Stuttgart, Germany
| | - 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
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15
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Mandal A, Hoque MA, Grupp A, Paretzki A, Kaim W, Lahiri GK. Analysis of Redox Series of Unsymmetrical 1,4-Diamido-9,10-anthraquinone-Bridged Diruthenium Compounds. Inorg Chem 2016; 55:2146-56. [DOI: 10.1021/acs.inorgchem.5b02541] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [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
| | - Md Asmaul Hoque
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai−400076, India
| | - Anita Grupp
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - Alexa Paretzki
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70550 Stuttgart, Germany
| | - 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
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16
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Mondal P, Das A, Lahiri GK. The Electron-Rich {Ru(acac)2} Directed Varying Configuration of the Deprotonated Indigo and Evidence for Its Bidirectional Noninnocence. Inorg Chem 2016; 55:1208-18. [DOI: 10.1021/acs.inorgchem.5b02409] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Prasenjit Mondal
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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17
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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.
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Affiliation(s)
- Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India.
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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
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Hazari AS, Das A, Ray R, Agarwala H, Maji S, Mobin SM, Lahiri GK. Tunable Electrochemical and Catalytic Features of BIAN- and BIAO-Derived Ruthenium Complexes. Inorg Chem 2015; 54:4998-5012. [PMID: 25928272 DOI: 10.1021/acs.inorgchem.5b00615] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This article deals with a class of ruthenium-BIAN-derived complexes, [Ru(II)(tpm)(R-BIAN)Cl]ClO4 (tpm = tris(1-pyrazolyl)methane, R-BIAN = bis(arylimino)acenaphthene, R = 4-OMe ([1a]ClO4), 4-F ([1b]ClO4), 4-Cl ([1c]ClO4), 4-NO2 ([1d]ClO4)) and [Ru(II)(tpm)(OMe-BIAN)H2O](2+) ([3a](ClO4)2). The R-BIAN framework with R = H, however, leads to the selective formation of partially hydrolyzed BIAO ([N-(phenyl)imino]acenapthenone)-derived complex [Ru(II)(tpm)(BIAO)Cl]ClO4 ([2]ClO4). The redox-sensitive bond parameters involving -N═C-C═N- or -N═C-C═O of BIAN or BIAO in the crystals of representative [1a]ClO4, [3a](PF6)2, or [2]ClO4 establish its unreduced form. The chloro derivatives 1a(+)-1d(+) and 2(+) exhibit one oxidation and successive reduction processes in CH3CN within the potential limit of ±2.0 V versus SCE, and the redox potentials follow the order 1a(+) < 1b(+) < 1c(+) < 1d(+) ≈ 2(+). The electronic structural aspects of 1a(n)-1d(n) and 2(n) (n = +2, +1, 0, -1, -2, -3) have been assessed by UV-vis and EPR spectroelectrochemistry, DFT-calculated MO compositions, and Mulliken spin density distributions in paramagnetic intermediate states which reveal metal-based (Ru(II) → Ru(III)) oxidation and primarily BIAN- or BIAO-based successive reduction processes. The aqua complex 3a(2+) undergoes two proton-coupled redox processes at 0.56 and 0.85 V versus SCE in phosphate buffer (pH 7) corresponding to {Ru(II)-H2O}/{Ru(III)-OH} and {Ru(III)-OH}/{Ru(IV)═O}, respectively. The chloro (1a(+)-1d(+)) and aqua (3a(2+)) derivatives are found to be equally active in functioning as efficient precatalysts toward the epoxidation of a wide variety of alkenes in the presence of PhI(OAc)2 as oxidant in CH2Cl2 at 298 K, though the analogous 2(+) remains virtually inactive. The detailed experimental analysis with the representative precatalyst 1a(+) suggests the involvement of the active {Ru(IV)═O} species in the catalytic cycle, and the reaction proceeds through the radical mechanism, as also supported by the DFT calculations.
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Affiliation(s)
- Arijit Singha Hazari
- †Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Ankita Das
- †Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Ritwika Ray
- †Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Hemlata Agarwala
- †Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Somnath Maji
- †Department of Chemistry, Indian Institute of Technology Bombay, Powai, 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, Powai, Mumbai 400076, India
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Mondal P, Ray R, Das A, Lahiri GK. Revelation of Varying Bonding Motif of Alloxazine, a Flavin Analogue, in Selected Ruthenium(II/III) Frameworks. Inorg Chem 2015; 54:3012-21. [DOI: 10.1021/acs.inorgchem.5b00122] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Prasenjit Mondal
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, India 400076
| | - Ritwika Ray
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, India 400076
| | - Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, India 400076
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, India 400076
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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.
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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
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Ghosh P, Ray R, Das A, Lahiri GK. Revelation of Varying Coordination Modes and Noninnocence of Deprotonated 2,2′-Bipyridine-3,3′-diol in {Os(bpy)2} Frameworks. Inorg Chem 2014; 53:10695-707. [DOI: 10.1021/ic501852a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Prabir Ghosh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Ritwika Ray
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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