1
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Sanfui S, Usman M, Roychowdhury A, Pramanik S, Garribba E, Gómez García CJ, Chen PPY, Rath SP. Bridge vs Terminal Cyano-coordination in Binuclear Cobalt Porphyrin Dimers: Interplay of Electrons between Metal and Ligand and Spin-Coupling via Bridge. Inorg Chem 2024; 63:15619-15633. [PMID: 39116010 DOI: 10.1021/acs.inorgchem.4c01150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2024]
Abstract
Three cyano-coordinated cobalt porphyrin dimers were synthesized and thoroughly characterized. The X-ray structure of the complexes reveals that cyanide binds in a terminal fashion in both the anti and trans isomers of ethane- and ethylene-bridged cobalt porphyrin dimers, while in the cis ethylene-bridged dimer, cyanides bind in both terminal and bridging modes. The nonconjugated ethane-bridged complex stabilizes exclusively a diamagnetic metal-centered oxidation of type CoIII(por)(CN)2 both in the solid and in solution. In contrast, the complexes with the conjugated ethylene-bridge contain signatures of both paramagnetic ligand-centered oxidation of the type CoII(por•+)(CN)2 and diamagnetic metal-centered oxidation of type CoIII(por)(CN)2 with the metal-centered oxidized species being the major component in the solid state as observed in XPS, while the ligand-centered oxidized species are present in a significant amount in solution. 1H NMR spectrum in solution displays two set of signals corresponding to the simultaneous presence of both the diamagnetic and paramagnetic species. EPR and magnetic investigation reveal that there is a moderate ferromagnetic coupling between the unpaired electrons of the low-spin CoII center and the porphyrin π-cation radical in CoII(por•+)(CN)2 species as well as an antiferromagnetic coupling between the two CoII(por•+) units through the ethylene and CN bridges.
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Affiliation(s)
- Sarnali Sanfui
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Mohammad Usman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Arya Roychowdhury
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Subhadip Pramanik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Eugenio Garribba
- Dipartimento di Medicina, Chirurgia e Farmacia, Viale San Pietro, Università di Sassari, Sassari I-07100, Italy
| | - Carlos J Gómez García
- Departamento de Química Inorgánica, Universidad de Valencia, C/Dr. Moliner 50, 46100 Burjassot, Valencia, Spain
| | - Peter P-Y Chen
- Department of Chemistry, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 402, Taiwan
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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2
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Sarkar S, Tiwari RK, Samanta D, Guchhait T, Sañudo EC, Rajaraman G, Rath SP. Unusual Stabilisation of Remarkably Bent Tetra-Cationic Tetra-radical Intermolecular Fe(III) μ-Oxo Tetranuclear Complexes. Angew Chem Int Ed Engl 2024; 63:e202402344. [PMID: 38478415 DOI: 10.1002/anie.202402344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Indexed: 04/24/2024]
Abstract
A hitherto unknown series of air stable, π-conjugated, remarkably bent tetra-cation tetra-radical intermolecular Fe(III) μ-oxo tetranuclear complex, isolated from the dication diradical diiron(III) porphyrin dimers, has been synthesised and spectroscopically characterised along with single crystal X-ray structure determination of two such molecules. These species facilitate long-range charge/radical delocalisation through the bridge across the entire tetranuclear unit manifesting an unusually intense NIR band. Assorted spin states of Fe(III) centres are stabilised within these unique tetranuclear frameworks: terminal six-coordinate iron centres stabilise the admixed intermediate spin states while the central five-coordinate iron centres stabilise the high-spin states. Variable temperature magnetic susceptibility measurements indicated strong antiferromagnetic coupling for the Fe(III)-O-Fe(III) unit while the exchange interactions between the Fe centres and the porphyrin π-cation radicals are weaker as supported both by magnetic data and DFT calculations. The nature of orbital overlap between the SOMOs of Fe(III) and π* orbital of the porphyrin was found to rationalise the observed exchange coupling, establishing such a complex magnetic exchange in this tetranuclear model with a significant bioinorganic relevance.
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Affiliation(s)
- Sabyasachi Sarkar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Rupesh Kumar Tiwari
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Deepannita Samanta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Tapas Guchhait
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - E Carolina Sañudo
- Secció de Química Inorgànica, Department de Química Inorgànica i Orgànica, Facultat de Química, Universitat de Barcelona, C/Martí i Franqués 1-11, 08028, Barcelona, Spain
- Institut de Nanociència i Nanotecnologia, IN2UB, Universitat de Barcelona, C/Martí i Franqués 1-11, 08028, Barcelona, Spain
| | - Gopalan Rajaraman
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
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3
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Shah SJ, Singh A, Goswami D, Ishida M, Rath SP. Reversible open-closed conformational switching of nano-size metalloporphyrin dimers triggered by light and temperature. Dalton Trans 2024; 53:6758-6765. [PMID: 38533553 DOI: 10.1039/d4dt00223g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
The current work demonstrates the reversible control of substantial molecular motion in 'nano-sized' molecules, where two structural isomers can 'open' and 'close' their cavities in response to light or heat. The isomers differ widely in their photophysical properties, including colour, polarity, two-photon absorption and π-conjugation, and can easily be separated through column chromatography and thus have wide applicability.
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Affiliation(s)
- Syed Jehanger Shah
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India.
| | - Ajitesh Singh
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India.
| | - Debabrata Goswami
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India.
| | - Masatoshi Ishida
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India.
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4
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Sanfui S, Roychowdhury A, Usman M, Garribba E, Gómez-García CJ, Rath SP. Metal vs Ligand Oxidation: Coexistence of Both Metal-Centered and Ligand-Centered Oxidized Species. Inorg Chem 2024; 63:5423-5431. [PMID: 38483819 DOI: 10.1021/acs.inorgchem.3c04043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
A series of two-electron-oxidized cobalt porphyrin dimers have been synthesized upon controlled oxidations using halogens. Rather unexpectedly, X-ray structures of two of these complexes contain two structurally different low-spin molecules in the same asymmetric unit of their unit cells: one is the metal-centered oxidized diamagnetic entity of the type CoIII(por), while the other one is the ligand-centered oxidized paramagnetic entity of the type CoII(por•+). Spectroscopic, magnetic, and DFT investigations confirmed the coexistence of the two very different electronic structures both in the solid and solution phases and also revealed a ferromagnetic spin coupling between Co(II) and porphyrin π-cation radicals and a weak antiferromagnetic coupling between the π-cation radicals of two macrocycles via the bridge in the paramagnetic complex.
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Affiliation(s)
- Sarnali Sanfui
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Arya Roychowdhury
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Mohammad Usman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Eugenio Garribba
- Dipartimento di Medicina, Chirurgia e Farmacia, Viale San Pietro, Università di Sassari, Sassari I-07100, Italy
| | - Carlos J Gómez-García
- Departamento de Química Inorgánica, Universidad de Valencia, C/Dr. Moliner 50, Burjasot, Valencia 46100, Spain
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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5
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Shah SJ, Pandit YA, Garribba E, Ishida M, Rath SP. Stable Dication Diradicals of Triply Fused Metallo Chlorin-Porphyrin Heterodimers: Impact of the Bridge on the Control of Spin Coupling to Reactivity. Chemistry 2023; 29:e202301963. [PMID: 37602834 DOI: 10.1002/chem.202301963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/16/2023] [Accepted: 08/16/2023] [Indexed: 08/22/2023]
Abstract
We report an unexpected rearrangement, controlled by the nature of the bridge, leading to the formation of novel, remarkably stable triply fused dinickel(II)/dicopper(II) chlorin-porphyrin dication diradical heterodimers in excellent yields. Here, a dipyrromethene bridge gets completely fused between two porphyrin macrocycles with two new C-C and one C-N bonds. The two macrocycles exhibit extensive π-conjugation through the bridge, which results in an antiferromagnetic coupling between the two π-cation radicals. In addition, the macrocyclic distortion also favours a rare intramolecular ferromagnetic interaction between the CuII and π-cation radical spins to form a triplet state. The structural and electronic perturbation in the unconjugated dication diradical possibly enables the bridging pyrrolic nitrogen to undergo a nucleophilic attack at the nearby β-carbon of the porphyrin π-cation radical with a computed free energy barrier of >20 kcal mol-1 which was supplied in the form of reflux condition to initiate such a rearrangement process. UV-vis, EPR and ESI-MS spectroscopies were used to monitor the rearrangement process in situ in order to identify the key reactive intermediates leading to such an unusual transformation.
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Affiliation(s)
- Syed Jehanger Shah
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Younis Ahmad Pandit
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Eugenio Garribba
- Dipartimento di Medicina, Chirurgia e Farmacia, Università di Sassari, Viale San Pietro, 07100, Sassari, Italy
| | - Masatoshi Ishida
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Tokyo, 192-0397, Japan
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
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6
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Pandit YA, Usman M, Sarkar A, Shah SJ, Rath SP. Control of spin coupling through a redox-active bridge in a dinickel(II) porphyrin dimer: step-wise oxidations enable isolations of a chlorin-porphyrin heterodimer and a dication diradical with a singlet ground state. Dalton Trans 2023; 52:877-891. [PMID: 36464989 DOI: 10.1039/d2dt03283j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A dinickel(II)porphyrin dimer has been used here in which the redox-active pyrrole-moiety, similar to the tryptophan residue in diheme enzymes such as MauG and bCcP, has been placed between two Ni(II)porphyrin centers connected via a flexible, but unconjugated methylene bridge. This arrangement provides a large physical separation between the two metal centers and thus displays almost no communication between them through the bridge. Upon treatment with DDQ as an oxidant, the dinickel(II) porphyrin dimer slowly gets converted into an indolizinium-fused chlorin-porphyrin heterodimer. However, oxidations of the dinickel(II) porphyrin dimer up to two oxidizing equivalents using oxidants such as AgSbF6 and FeCl3 resulted in the formation of a dication diradical complex. Interestingly, in order to stabilize such a highly oxidized dication diradical, two non-conjugated methylene spacers undergo facile 2e-/-2H+ oxidation to make the bridge fully π-conjugated for promoting through-bond communication. Through the oxidized and conjugated bridge, two porphyrin π-cation radicals display considerable communications leading to an efficient intramolecular spin coupling to form a singlet state. Interestingly, the redox-active nature of the bridge controls the electronic communication just by simple oxidation or reduction, and thereby, acts as a molecular switch for efficient magnetic relay.
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Affiliation(s)
- Younis Ahmad Pandit
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India.
| | - Mohammad Usman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India.
| | - Anindya Sarkar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India.
| | - Syed Jehanger Shah
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India.
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India.
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7
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Sil D, Khan FST, Rath SP. Effect of intermacrocyclic interactions: Modulation of metal spin-state in oxo/hydroxo/fluoro-bridged diiron(III)/dimanganese(III) porphyrin dimers. ADVANCES IN INORGANIC CHEMISTRY 2023. [DOI: 10.1016/bs.adioch.2022.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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8
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Mizrahi A, Bhowmik S, Manna AK, Sinha W, Kumar A, Saphier M, Mahammed A, Patra M, Fridman N, Zilbermann I, Kronik L, Gross Z. Electronic Coupling and Electrocatalysis in Redox Active Fused Iron Corroles. Inorg Chem 2022; 61:20725-20733. [PMID: 36512733 PMCID: PMC9799712 DOI: 10.1021/acs.inorgchem.2c01389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Conjugated arrays composed of corrole macrocycles are increasingly more common, but their chemistry still lags behind that of their porphyrin counterparts. Here, we report on the insertion of iron(III) into a β,β-fused corrole dimer and on the electronic effects that this redox active metal center has on the already rich coordination chemistry of [H3tpfc] COT, where COT = cyclo-octatetraene and tpfc = tris(pentafluorophenyl)corrole. Synthetic manipulations were performed for the isolation and full characterization of both the 5-coordinate [FeIIItpfc(py)]2COT and 6-coordinate [FeIIItpfc(py)2]2COT, with one and two axial pyridine ligands per metal, respectively. X-Ray crystallography reveals a dome-shaped structure for [FeIIItpfc(py)]2COT and a perfectly planar geometry which (surprisingly at first) is also characterized by shorter Fe-N (corrole) and Fe-N (pyridine) distances. Computational investigations clarify that the structural phenomena are due to a change in the iron(III) spin state from intermediate (S = 3/2) to low (S = 1/2), and that both the 5- and 6-coordinated complexes are enthalpically favored. Yet, in contrast to iron(III) porphyrins, the formation enthalpy for the coordination of the first pyridine to Fe(III) corrole is more negative than that of the second pyridine coordination. Possible interactions between the two corrole subunits and the chelated iron ions were examined by UV-Vis spectroscopy, electrochemical techniques, and density functional theory (DFT). The large differences in the electronic spectra of the dimer relative to the monomer are concluded to be due to a reduced electronic gap, owing to the extensive electron delocalization through the fusing bridge. A cathodic sweep for the dimer discloses two redox processes, separated by 230 mV. The DFT self-consistent charge density for the neutral and cationic states (1- and 2-electron oxidized) reveals that the holes are localized on the macrocycle. A different picture emerges from the reduction process, where both the electrochemistry and the calculated charge density point toward two consecutive electron transfers with similar energetics, indicative of very weak electron communication between the two redox active iron(III) sites. The binuclear complex was determined to be a much better catalyst for the electrochemical hydrogen evolution reaction (HER) than the analogous mononuclear corrole.
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Affiliation(s)
- Amir Mizrahi
- Chemistry
Department, Nuclear Research Centre Negev, Beer-Sheva84190, Israel,Schulich
Faculty of Chemistry, Technion Institute
of Technology, Haifa3200003, Israel
| | - Susovan Bhowmik
- Schulich
Faculty of Chemistry, Technion Institute
of Technology, Haifa3200003, Israel,Bankura
Sammilani College (W.B), Bankura722102, India
| | - Arun K. Manna
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot76100, Israel
| | - Woormileela Sinha
- Schulich
Faculty of Chemistry, Technion Institute
of Technology, Haifa3200003, Israel,Department
of Chemistry, BITS PilaniK K Birla Goa Campus, NH17B, Zuarinagar, Goa403726, India
| | - Amit Kumar
- Schulich
Faculty of Chemistry, Technion Institute
of Technology, Haifa3200003, Israel
| | - Magal Saphier
- Chemistry
Department, Nuclear Research Centre Negev, Beer-Sheva84190, Israel
| | - Atif Mahammed
- Schulich
Faculty of Chemistry, Technion Institute
of Technology, Haifa3200003, Israel
| | | | - Natalia Fridman
- Schulich
Faculty of Chemistry, Technion Institute
of Technology, Haifa3200003, Israel
| | - Israel Zilbermann
- Chemistry
Department, Nuclear Research Centre Negev, Beer-Sheva84190, Israel,Chemistry
Department, Ben-Gurion University of the
Negev, Beer-Sheva84105, Israel,
| | - Leeor Kronik
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot76100, Israel,
| | - Zeev Gross
- Schulich
Faculty of Chemistry, Technion Institute
of Technology, Haifa3200003, Israel,
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9
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Sarkar S, Sarkar P, Samanta D, Pati SK, Rath SP. Cooperativity in Diiron(III)porphyrin Dication Diradical-Catalyzed Oxa-Diels–Alder Reactions: Spectroscopic and Mechanistic Insights. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sabyasachi Sarkar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Pallavi Sarkar
- Theoretical Sciences Unit, School of Advanced Materials (SAMat), Jawaharlal Nehru Center for Advanced Scientific Research, Bangalore 560064, India
| | - Deepannita Samanta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Swapan K Pati
- Theoretical Sciences Unit, School of Advanced Materials (SAMat), Jawaharlal Nehru Center for Advanced Scientific Research, Bangalore 560064, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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10
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Sanfui S, Usman M, Sarkar S, Pramanik S, Garribba E, Rath SP. Highly Oxidized Cobalt Porphyrin Dimer: Control of Spin Coupling via a Bridge. Inorg Chem 2022; 61:8419-8430. [PMID: 35613476 DOI: 10.1021/acs.inorgchem.1c03807] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A cobalt porphyrin dimer is constructed in which two Co(II)porphyrins are connected covalently through a redox-active diethylpyrrole moiety via a flexible but "nonconjugated" methylene bridge. Upon oxidation with even a mild oxidant such as iodine, each cobalt(II) center and porphyrin ring undergo 1e- oxidation, leading to the formation of a 4e--oxidized cobalt(III)porphyrin dication diradical complex. Other oxidants such as Cl2 and Br2 also produce similar results. To stabilize such highly oxidized dication diradicals, the "nonconjugated" methylene spacer undergoes a facile and spontaneous oxidation to form a methine group with a drastic structural change, thereby making the bridge fully π-conjugated and enabling through-bond communication. This results in a strong spin coupling between two π-cation radicals which stabilizes the singlet state. The experimental observations are also strongly supported by extensive density functional theory calculations. The present study highlights the crucial role played by the nature of the bridge in the long-range electronic communication.
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Affiliation(s)
- Sarnali Sanfui
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Mohammad Usman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sabyasachi Sarkar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Subhadip Pramanik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Eugenio Garribba
- Dipartimento di Scienze Mediche, Chirurgiche e Sperimentali, Università di Sassari, Viale San Pietro, Sassari I-07100, Italy
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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11
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Pandit YA, Shah SJ, Usman M, Sarkar S, Garribba E, Rath SP. Long-Range Intramolecular Spin Coupling through a Redox-Active Bridge upon Stepwise Oxidations: Control and Effect of Metal Ions. Inorg Chem 2022; 61:5270-5282. [PMID: 35323011 DOI: 10.1021/acs.inorgchem.1c03945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dinickel(II) and dicopper(II) porphyrin dimers have been constructed in which two metalloporphyrin units are widely separated by a long unconjugated dipyrrole bridge. Two macrocycles are aligned somewhat orthogonally to each other, while oxidation of the bridge generates a fully π-conjugated butterfly-like structure, which, in turn, upon stepwise oxidations by stronger oxidants result in the formation of the corresponding one- and two-electron-oxidized species exhibiting unusual long-range charge/radical delocalization to produce intense absorptions in the near-infrared (NIR) region and electron paramagnetic resonance (EPR) signals of a triplet state due to interaction between the unpaired spins on the Cu(II) ions. Although the two metal centers have a large physical separation through the bridge (more than 16 Å), they share electrons efficiently between them, behaving as a single unit rather than two independent centers. Detailed UV-vis-NIR, electrospray ionization mass spectrometry, IR, variable-temperature magnetic study, and EPR spectroscopic investigations along with X-ray structure determination of unconjugated, conjugated, and one electron-oxidized complexes have been exploited to demonstrate the long-range electronic communication through the bridge. The experimental observations are also supported by density functional theory (DFT) and time-dependent DFT calculations. The present study highlights the crucial roles played by a redox-active bridge and metal in controlling the long-range electronic communication.
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Affiliation(s)
- Younis Ahmad Pandit
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Syed Jehanger Shah
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Mohammad Usman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sabyasachi Sarkar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Eugenio Garribba
- Dipartimento di Scienze Mediche, Chirurgiche e Sperimentali, Università di Sassari, Viale San Pietro, Sassari I-07100, Italy
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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12
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Singh AK, Usman M, Sarkar S, Sciortino G, Kumar D, Garribba E, Rath SP. Ferromagnetic Coupling in Oxidovanadium(IV)-Porphyrin Radical Dimers. Inorg Chem 2021; 60:16492-16506. [PMID: 34664950 DOI: 10.1021/acs.inorgchem.1c02331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three different oxidovanadium(IV) porphyrin dimers with anti, cis, and trans arrangements of the two rings have been synthesized by changing the bridge between the porphyrin macrocycles. This provides a unique opportunity to investigate the role of the bridge and spatial arrangement between the two VIVO centers for their electronic communication and magnetic coupling. They were characterized by the combined application of XRD analysis, UV-vis and electron paramagnetic resonance (EPR) spectroscopy, cyclic voltammetry, magnetic susceptibility, and DFT calculations. One- and two-electron oxidations produce mono- and dication diradical species, respectively, which display an unusual ferromagnetic interaction between the unpaired spins of vanadium(IV) and porphyrin π-cation radical, in contrast to other metalloporphyrin dimers. The oxidized species show a dissimilar behavior between cis and trans isomers. The ferromagnetic coupling occurs between the porphyrin π-cation radical and the unpaired electron of the VIVO ion on the dxy orbital, orthogonal to the porphyrin-based molecular orbitals a1u and a2u.
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Affiliation(s)
- Akhil Kumar Singh
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Mohammad Usman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sabyasachi Sarkar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Giuseppe Sciortino
- Dipartimento di Chimica e Farmacia, Università di Sassari, Via Vienna 2, I-07100 Sassari, Italy.,Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology (BIST), 43007 Tarragona, Spain
| | - Devesh Kumar
- Department of Physics, School for Physical and Decision Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow 226025, India
| | - Eugenio Garribba
- Dipartimento di Chimica e Farmacia, Università di Sassari, Via Vienna 2, I-07100 Sassari, Italy
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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13
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Khan FST, Samanta D, Chandel D, Shah SJ, Rath SP. Heme-Heme Interactions in Diheme Cytochromes: Effect of Mixed-Axial Ligation on the Electronic Structure and Electrochemical Properties. Inorg Chem 2021; 60:12870-12882. [PMID: 34370470 DOI: 10.1021/acs.inorgchem.1c01215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Diheme cytochromes, the simplest members in the multiheme family, play substantial biochemical roles in enzymatic catalysis as well as in electron transfer. A series of diiron(III) porphyrin dimers have been synthesized as active site analogues of diheme cytochromes. The complexes contain six-coordinated iron(III) having thiophenol and imidazole at the fifth and sixth coordination sites, respectively. The iron centers in the complexes have been found to be in a low-spin state, as confirmed through solid-state Mössbauer and electron paramagnetic resonance (EPR) spectroscopic investigations. Mössbauer quadrupole splitting of complexes having mixed ligands is substantially larger than that observed when both axial ligands are the same. Rhombic types of EPR spectra with narrow separation between gx, gy, and gz clearly distinguish heme thiolate coordination compared to bis(imidazole)-ligated low-spin heme centers. The redox potential in diheme cytochromes has been found to be tuned by interheme interactions along with the nature of axial ligands. The effect of mixed-axial ligation within the diiron(III) porphyrin dimers is demonstrated by a positive shift in the Fe(III)/Fe(II) redox couple upon thiophenolate coordination compared to their bis(imidazole) analogues. The pKa of the imidazole also decides the extent of the shift for the Fe(III)/Fe(II) couple, while the potential of the mixed-ligated diiron(III) porphyrin dimer is more positive compared to their monomeric analogue. A variation of around 1.1 V for the Fe(III)/Fe(II) redox potential in the diiron(III) porphyrin dimer can be achieved with the combined effect of axial ligation and a metal spin state, while such a large variation in the redox potential, compared to their monomeric analogues, is attributed to the heme-heme interactions observed in dihemes. Moreover, theoretical calculations also support the experimental shifts in the redox potential values.
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Affiliation(s)
| | - Deepannita Samanta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Dolly Chandel
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Syed Jehanger Shah
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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14
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Kumar A, Usman M, Samanta D, Rath SP. Through Bridge Spin Coupling in Homo- and Heterobimetallic Porphyrin Dimers upon Stepwise Oxidations: A Spectroscopic and Theoretical Investigation. Chemistry 2021; 27:11428-11441. [PMID: 34061401 DOI: 10.1002/chem.202101384] [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: 04/16/2021] [Indexed: 12/16/2022]
Abstract
We have described copper(II)-iron(III) and copper(II)-manganese(III) heterobimetallic porphyrin dimers and compared them with the corresponding homobimetallic analogs. UV-visible spectra are very distinct in the heterometallic species while electrochemical studies demonstrate that these species, as compared to the homobimetallic analog, are much easier to oxidize. Combined Mössbauer, EPR, NMR, magnetic and UV-visible spectroscopic studies show that upon 2e-oxidation of the heterobimetallic complexes only ring-centered oxidation occurs. The energy differences between HOMO and LUMO are linearly dependent with the low-energy NIR band obtained for the 2e-oxidized complexes. Also, strong electronic communication between two porphyrin rings through the bridge facilitates coupling between various unpaired spins present while the coupling model depends on the nature of metal ions used. While unpaired spins of Fe(III) and the porphyrin π-cation radical are strongly antiferromagnetically coupled, such coupling is rather weak between Mn(III) and a porphyrin π-cation radical. Moreover, the coupling between two π-cation radicals are much stronger in the 2e-oxidized complexes of dimanganese(III) and copper(II)-manganese(III) porphyrin dimers as compared to their diiron(III) and copper(II)-iron(III) analogs. Furthermore, coupling between the unpaired spins of a π-cation radical and copper(II) is much stronger in the 2e-oxidized complex of copper(II)-iron(III) porphyrin dimer as compared to its copper(II)-manganese(III) analog. The Mulliken spin density distributions in 2e-oxidized homo- and heterobimetallic complexes show symmetric and asymmetric spread between the two macrocycles, respectively. In both the 2e-oxidized heterobimetallic complexes, the Cu(II) porphyrin center acts as a charge donor while Fe(III)/Mn(III) porphyrin center act as a charge acceptor. The experimental observations are also strongly supported by DFT calculations.
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Affiliation(s)
- Amit Kumar
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Mohammad Usman
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Deepannita Samanta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
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15
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Singh AK, Rath SP. Intermacrocyclic Interactions upon Stepwise Oxidations in a Monometallic Porphyrin Dimer: Ring versus Metal‐Center Oxidations and Effect of Counter Anions. Chemistry 2020; 26:14405-14418. [DOI: 10.1002/chem.202002188] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 06/15/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Akhil Kumar Singh
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 India
| | - Sankar Prasad Rath
- Department of Chemistry Indian Institute of Technology Kanpur Kanpur 208016 India
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16
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Kumar A, Sanfui S, Sciortino G, Maréchal J, Garribba E, Rath SP. Stepwise Oxidations in a Cofacial Copper(II) Porphyrin Dimer: Through‐Space Spin‐Coupling and Interplay between Metal and Radical Spins. Chemistry 2020; 26:7869-7880. [DOI: 10.1002/chem.202000348] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/06/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Amit Kumar
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Sarnali Sanfui
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Giuseppe Sciortino
- Dipartimento di Chimica e FarmaciaUniversità di Sassari Via Vienna 2 07100 Sassari Italy
- Departament de QuímicaUniversitat Autònoma de Barcelona 08193 Cerdanyola del Vallés Barcelona Spain
| | - Jean‐Didier Maréchal
- Departament de QuímicaUniversitat Autònoma de Barcelona 08193 Cerdanyola del Vallés Barcelona Spain
| | - Eugenio Garribba
- Dipartimento di Chimica e FarmaciaUniversità di Sassari Via Vienna 2 07100 Sassari Italy
| | - Sankar Prasad Rath
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
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17
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Sahoo D, Roy S, Khan FST, Singh AK, Rath SP. Stabilizing intermediate-spin state in iron(III) porphyrins. Polyhedron 2019. [DOI: 10.1016/j.poly.2019.02.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Wang Q, Song M, Song X, Bu Y. Unexpected diradical character and large magnetic spin coupling in modified porphyrins induced by inverting pyrrole rings. Phys Chem Chem Phys 2019; 21:17209-17220. [PMID: 31343647 DOI: 10.1039/c9cp02691f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Porphyrin derivatives with inverted pyrrole rings have been experimentally synthesized, and their relevant electronic and magnetic properties have great application prospects in terms of electronic devices. In this work, we rationally design the structures and computationally investigate the electronic properties of porphine and Mg/Zn-porphyrin derivatives with two inverted pyrrole rings, i.e. the dipyrrole-inverted porphine and Mg/Zn-porphyrin analogues (1NN-2H, 2NN-2H, 1NN-Mg, 2NN-Mg, 1NN-Zn and 2NN-Zn), at the B3LYP/6-311G(d,p) level. The main structural characters of these porphyrin derivatives are that the [double bond splayed left]NH units of two pyrrole rings are inverted outwards and the porphyrin-like macrocycles are distorted from square to diamond shapes. More interestingly, these dipyrrole-inverted porphyrin derivatives present diradical characters with noticeably large antiferromagnetic spin coupling constants, i.e.-982.2/-936.3 cm-1 for 1NN-2H/2NN-2H, -796.3/-764.2 cm-1 for 1NN-Mg/2NN-Mg and -1044.5/-1055.2 cm-1 for 1NN-Zn/2NN-Zn, but their monopyrrole-inverted counterparts do not. Examinations of the orbital properties featuring large occupation numbers of the lowest unoccupied natural orbitals and two singly occupied molecular orbitals that are polarized in opposite directions also confirm these findings. These porphyrin derivatives have small singlet-triplet energy gaps and small energy gaps between the highest occupied molecular orbital and lowest unoccupied molecular orbital of the closed-shell singlet states. These are conducive to the emergence of diradical character and large spin coupling constants. Furthermore, the spin-alternation analyses show that each dipyrrole-inverted porphyrin derivative has two resonant structures featuring two spin-opposite single electrons, in agreement with the observed antiferromagnetic spin couplings. This work provides novel insights into the electronic structures and properties of the porphyrin derivatives with modified structures and also provides helpful information for the rational design, synthesis and characterization of new porphyrin-based magnets.
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Affiliation(s)
- Qi Wang
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, People's Republic of China.
| | - Meiyu Song
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, People's Republic of China.
| | - Xinyu Song
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, People's Republic of China.
| | - Yuxiang Bu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, People's Republic of China.
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19
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Axial ligand mediated switchable rotary motions in a ferrocene-bridged diiron(III) porphyrin dimer. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2019.05.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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20
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Singh AK, Usman M, Sciortino G, Garribba E, Rath SP. Through‐Space Spin Coupling in a Silver(II) Porphyrin Dimer upon Stepwise Oxidations: Ag
II
⋅⋅⋅Ag
II
, Ag
II
⋅⋅⋅Ag
III
, and Ag
III
⋅⋅⋅Ag
III
Metallophilic Interactions. Chemistry 2019; 25:10098-10110. [DOI: 10.1002/chem.201901731] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 05/17/2019] [Indexed: 12/25/2022]
Affiliation(s)
- Akhil Kumar Singh
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Mohammad Usman
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Giuseppe Sciortino
- Dipartimento di Chimica e FarmaciaUniversità di Sassari Via Vienna 2 07100 Sassari Italy
- Departament de QuímicaUniversitat Autònoma de Barcelona 08193 Cerdanyola del Vallés Barcelona Spain
| | - Eugenio Garribba
- Dipartimento di Chimica e FarmaciaUniversità di Sassari Via Vienna 2 07100 Sassari Italy
| | - Sankar Prasad Rath
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
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21
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Khan FST, Kumar A, Lai D, Rath SP. Ethene-bridged diiron porphyrin dimer as models of diheme cytochrome c: Structure-function correlation and modulation of heme redox potential. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.09.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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22
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Khan FST, Shah SJ, Bhowmik S, Reinhard FGC, Sainna MA, de Visser SP, Rath SP. Equatorial ligand plane perturbations lead to a spin-state change in an iron(iii) porphyrin dimer. Dalton Trans 2019; 48:6353-6357. [DOI: 10.1039/c9dt01182j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A complete reversal of the spin state of iron(iii) is observed upon a small change to the diporphyrin bridge from ethane to ethene by keeping all other factors intact.
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Affiliation(s)
| | - Syed Jehanger Shah
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Susovan Bhowmik
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Fabián G. Cantú Reinhard
- The Manchester Institute of Biotechnology and the School of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
| | - Mala A. Sainna
- The Manchester Institute of Biotechnology and the School of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
| | - Sam P. de Visser
- The Manchester Institute of Biotechnology and the School of Chemical Engineering and Analytical Science
- The University of Manchester
- Manchester M1 7DN
- UK
| | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
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23
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Kumar A, Sil D, Usman M, Rath SP. A dimanganese(iii) porphyrin dication diradical and its transformation to a μ-hydroxo porphyrin–oxophlorin heterodimer. Chem Commun (Camb) 2019; 55:1588-1591. [DOI: 10.1039/c8cc09366k] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Spin coupling models are different between iron and manganese in their dication diradical complexes, which is reflected in their reactivity as shown.
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Affiliation(s)
- Amit Kumar
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Debangsu Sil
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Mohammad Usman
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
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24
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Kumar A, Banerjee S, Sarkar S, Rath SP. Stepwise oxidations of a nickel(ii)–iron(iii) heterobimetallic porphyrin dimer: structure, spectroscopic and theoretical investigation. Dalton Trans 2019; 48:10089-10103. [DOI: 10.1039/c9dt01776c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel nickel(ii)–iron(iii) heterobimetallic ethene-bridged porphyrin dimer has been synthesized which upon two-electron oxidation produces a nickel(ii)–iron(iii) dication diradical complex where radicals undergo extensive conjugation through the bridge for all possible interactions.
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Affiliation(s)
- Amit Kumar
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Sayantani Banerjee
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Sabyasachi Sarkar
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
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25
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Pandey AK, Usman M, Rath SP. A counter ion triggers stabilization of two geometrical isomers of a Ni(ii) dication diradical porphyrin dimer: the role of anion–π interactions. Chem Commun (Camb) 2019; 55:7926-7929. [DOI: 10.1039/c9cc02902h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two isomers of a nickel(ii)porphyrinato dication diradical, isolated selectively in pure form, are stabilized exclusively by anion–π interactions, have unique and distinct electronic and spectroscopic features and display an anion-induced charge/electron transfer phenomenon.
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Affiliation(s)
- Anjani Kumar Pandey
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Mohammad Usman
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
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26
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Wei H, Feng R, Fang Y, Wang L, Chen C, Zhang L, Cui H, Wang X. The Diradical-Dication Strategy for BODIPY- and Porphyrin-Based Dyes with Near-Infrared Absorption Maxima from 1070 to 2040 nm. Chemistry 2018; 24:19341-19347. [PMID: 30285312 DOI: 10.1002/chem.201804449] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/26/2018] [Indexed: 01/10/2023]
Abstract
Four stable boron dipyrromethene (BODIPY)- and porphyrin-based bis-arylamine diradical dications were synthesized by two-electron oxidation of their neutral molecules. The two BODIPY-based dications have open-shell singlet ground states. UV/Vis absorption spectra of all four dications showed large redshifts in the NIR region compared to their neutral precursors with absorption maxima at 1274 and 1068 nm for the two BODIPY-based dications and 1746 and 2037 nm for the two porphyrin-based dications. Thus, two new types of NIR dyes with longer wavelengths are provided by the diradical-dication strategy, which can be applied for the generation of other NIR dyes with a range of different chromophores and auxochromes.
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Affiliation(s)
- Houjia Wei
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Rui Feng
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Yong Fang
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Lei Wang
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Chao Chen
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Li Zhang
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Haiyan Cui
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China.,Jiangsu Key Laboratory of Pesticide Science, College of Sciences, Nanjing Agricultural University, Nanjing, 210095, P. R. China
| | - Xinping Wang
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
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27
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Khan FST, Banerjee S, Kumar D, Rath SP. Diheme Cytochrome c: Structure–Function Correlation and Effect of Heme−Heme Interactions. Inorg Chem 2018; 57:11498-11510. [DOI: 10.1021/acs.inorgchem.8b01368] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Sayantani Banerjee
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Devesh Kumar
- Department of Physics, School for Physical and Decision Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow-226025, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
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28
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Pandit YA, Shah SJ, Rath SP. Unusual Stabilization of Dication Diradical Intermediate of Dizinc(II) Porphyrin Dimer. Z Anorg Allg Chem 2018. [DOI: 10.1002/zaac.201800247] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Younis Ahmad Pandit
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
| | - Syed Jehanger Shah
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
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29
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Modulation of iron spin in ethane-bridged diiron(III) porphyrin dimer: anion dependent spin state switching. J CHEM SCI 2018. [DOI: 10.1007/s12039-018-1488-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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30
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Lai D, Khan FST, Rath SP. Multiheme proteins: effect of heme–heme interactions. Dalton Trans 2018; 47:14388-14401. [DOI: 10.1039/c8dt00518d] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This Frontier illustrates a brief personal account on the effect of heme–heme interactions in dihemes which thereby discloses some of the evolutionary design principles involved in multiheme proteins for their diverse structures and functions.
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Affiliation(s)
- Dipti Lai
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | | | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
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31
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Pandit YA, Sanfui S, Rath SP. Intermacrocyclic Interaction Triggers Facile One-Pot Synthesis of a Chlorin-Porphyrin Heterodimer. Chemistry 2017; 23:13415-13422. [DOI: 10.1002/chem.201701943] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Indexed: 01/16/2023]
Affiliation(s)
- Younis Ahmad Pandit
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur 208016 India
| | - Sarnali Sanfui
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur 208016 India
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur 208016 India
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32
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Guchhait T, Sarkar S, Pandit YA, Rath SP. Probing Bis‐FeIVMauG: Isolation of Highly Reactive Radical Intermediates. Chemistry 2017; 23:10270-10275. [DOI: 10.1002/chem.201702321] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Tapas Guchhait
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Sabyasachi Sarkar
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Younis Ahmad Pandit
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
| | - Sankar Prasad Rath
- Department of ChemistryIndian Institute of Technology Kanpur Kanpur 208016 India
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33
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Singh AK, Khan FST, Rath SP. Silver(III)⋅⋅⋅Silver(III) Interactions that Stabilize the syn
Form in a Porphyrin Dimer Upon Oxidation. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201705108] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Akhil Kumar Singh
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | | | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
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34
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Singh AK, Khan FST, Rath SP. Silver(III)⋅⋅⋅Silver(III) Interactions that Stabilize the syn
Form in a Porphyrin Dimer Upon Oxidation. Angew Chem Int Ed Engl 2017; 56:8849-8854. [DOI: 10.1002/anie.201705108] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Akhil Kumar Singh
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | | | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
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35
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Oxo- and hydroxo-bridged diiron(III) porphyrin dimers: Inorganic and bio-inorganic perspectives and effects of intermacrocyclic interactions. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2017.02.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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36
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Tanaka T, Ooi S, Ide Y, Ikeue T, Suzuki M, Chen PP, Takahashi M, Osuka A. Different Antiferromagnetic Coupling between 5,5′‐ and 10,10′‐Linked Iron(III) Corrole Dimers. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201601363] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Takayuki Tanaka
- Department of Chemistry Graduate School of Science Kyoto University 606‐8502 Sakyo‐ku, Kyoto Japan
| | - Shota Ooi
- Department of Chemistry Graduate School of Science Kyoto University 606‐8502 Sakyo‐ku, Kyoto Japan
| | - Yuki Ide
- Department of Chemistry, Graduate School of Science and Engineering Shimane University 1060 Nishikawatsu, Matsue 690‐8504 Japan
| | - Takahisa Ikeue
- Department of Chemistry, Graduate School of Science and Engineering Shimane University 1060 Nishikawatsu, Matsue 690‐8504 Japan
| | - Masaaki Suzuki
- Department of Chemistry, Graduate School of Science and Engineering Shimane University 1060 Nishikawatsu, Matsue 690‐8504 Japan
| | - Peter P.‐Y. Chen
- Department of Chemistry National Chung Hsing University Taichung 402 Taiwan Republic of China
| | - Masashi Takahashi
- Department of Chemistry Faculty of Science and Research Center for Materials with Integrated Properties 274‐8510 Toho University Japan
| | - Atsuhiro Osuka
- Department of Chemistry Graduate School of Science Kyoto University 606‐8502 Sakyo‐ku, Kyoto Japan
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Bhowmik S, Kosa M, Mizrahi A, Fridman N, Saphier M, Stanger A, Gross Z. The Planar Cyclooctatetraene Bridge in Bis-Metallic Macrocycles: Isolating or Conjugating? Inorg Chem 2017; 56:2287-2296. [PMID: 28182414 DOI: 10.1021/acs.inorgchem.6b02944] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A minor modification of the reported procedure for the synthesis of a corrole dimer that is fused by the cyclooctatetraene (COT) unit, (H3tpfc)2COT, allowed for its isolation in 18% yield. Of the two redox isomers that this interesting macrocycle does form, the current focus is on the reduced form, in which each subunit resembles that of monomeric corroles with a trianionic N4 coordination core. The corresponding bis-gallium(III) complex was prepared as an entry into the potentially rich coordination chemistry of (H3tpfc)2COT. Both X-ray crystallography and DFT calculations disclosed that the COT moiety is essentially planar with very unusual nonalternating C-C bonds. The same holds true for the bis-gallium(III) complexes [(Ga-tpfc)2]COT(py)2 and [(Ga-tpfc)2]COT(py)4, obtained with one and two pyridine molecules coordinated to each metal ion, respectively. The electronic spectra of both the free base and the gallium(III) complexes display an extremely low energy band (λmax at 720-724 nm), which points toward extensive π delocalization through the COT bridge. This aspect was fully addressed by examining the interactions between the two corrole subunits in terms of electrochemistry and DFT calculations of the oxidized and reduced macrocycle. The new near-IR bands that appear upon both oxidation (λmax 1250 nm) and reduction (λmax 1780 nm) serve as additional supporting evidence for this conclusion.
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Affiliation(s)
- Susovan Bhowmik
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology , Haifa 32000, Israel
| | - Monica Kosa
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology , Haifa 32000, Israel
| | - Amir Mizrahi
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology , Haifa 32000, Israel.,Chemistry Department, Nuclear Research Centre Negev , Beer-Sheva, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology , Haifa 32000, Israel
| | - Magal Saphier
- Chemistry Department, Nuclear Research Centre Negev , Beer-Sheva, Israel
| | - Amnon Stanger
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology , Haifa 32000, Israel
| | - Zeev Gross
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology , Haifa 32000, Israel
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Khan FST, Guchhait T, Sasmal S, Rath SP. Hydroxo-bridged diiron(iii) and dimanganese(iii) bisporphyrins: modulation of metal spins by counter anions. Dalton Trans 2017; 46:1012-1037. [DOI: 10.1039/c6dt03829h] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A brief account has been presented on how the inter-heme interactions in μ-hydroxo diiron(iii) bisporphyrins and counter anions can induce significant change in the structure and properties including the iron spin state without affecting the overall topology.
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Affiliation(s)
| | - Tapas Guchhait
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Sujit Sasmal
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
| | - Sankar Prasad Rath
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur-208016
- India
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39
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Khan FST, Pandey AK, Rath SP. Remarkable Anion-Dependent Spin-State Switching in Diiron(III) μ-Hydroxo Bisporphyrins: What Role do Counterions Play? Chemistry 2016; 22:16124-16137. [PMID: 27682429 DOI: 10.1002/chem.201603163] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Indexed: 12/20/2022]
Abstract
Addition of 2,4,6-trinitrophenol (HTNP) to an ethene-bridged diiron(III) μ-oxo bisporphyrin (1) in CH2 Cl2 initially leads to the formation of diiron(III) μ-hydroxo bisporphyrin (2⋅TNP) with a phenolate counterion that, after further addition of HTNP or dissolution in a nonpolar solvent, converts to a diiron(III) complex with axial phenoxide coordination (3⋅(TNP)2 ). The progress of the reaction from μ-oxo to μ-hydroxo to axially ligated complex has been monitored in solution by using 1 H NMR spectroscopy because their signals appear in three different and distinct spectral regions. The X-ray structure of 2⋅TNP revealed that the nearly planar TNP counterion fits perfectly within the bisporphyrin cavity to form a strong hydrogen bond with the μ-hydroxo group, which thus stabilizes the two equivalent iron centers. In contrast, such counterions as I5 , I3 , BF4 , SbF6 , and PF6 are found to be tightly associated with one of the porphyrin rings and, therefore, stabilize two different spin states of iron in one molecule. A spectroscopic investigation of 2⋅TNP has revealed the presence of two equivalent iron centers with a high-spin state (S=5/2) in the solid state that converts to intermediate spin (S=3/2) in solution. An extensive computational study by using a range of DFT methods was performed on 2⋅TNP and 2+ , and clearly supports the experimentally observed spin flip triggered by hydrogen-bonding interactions. The counterion is shown to perturb the spin-state ordering through, for example, hydrogen-bonding interactions, switched positions between counterion and axial ligand, ion-pair interactions, and charge polarization. The present investigation thus provides a clear rationalization of the unusual counterion-specific spin states observed in the μ-hydroxo bisporphyrins that have so far remained the most outstanding issue.
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Affiliation(s)
| | - Anjani Kumar Pandey
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
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Sil D, Khan FST, Rath SP. Effect of Inter-Porphyrin Distance on Spin-State in Diiron(III) μ-Hydroxo Bisporphyrins. Chemistry 2016; 22:14585-97. [DOI: 10.1002/chem.201602018] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Indexed: 12/16/2022]
Affiliation(s)
- Debangsu Sil
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | | | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
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41
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Sil D, Kumar A, Rath SP. Diiron(III)-μ-Fluoro Bisporphyrins: Effect of Bridging Ligand on the Metal Spin State. Chemistry 2016; 22:11214-23. [DOI: 10.1002/chem.201600786] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Debangsu Sil
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | - Amit Kumar
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
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42
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Sahoo D, Guchhait T, Rath SP. Spin Modulation in Highly Distorted FeIIIPorphyrinates by Using Axial Coordination and Their π-Cation Radicals. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600255] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dipankar Sahoo
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
| | - Tapas Guchhait
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
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Sahoo D, Singh AK, Rath SP. Binuclear Highly Distorted Iron(III) Porphyrins Bridged by the Dianions of Hydroquinones: Role of the Bridge in Electronic Communication. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600257] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dipankar Sahoo
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
| | - Akhil Kumar Singh
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; 208016 Kanpur India
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44
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Sil D, Bhowmik S, Khan FST, Rath SP. Experimental and Theoretical Investigation of a Series of Novel Dimanganese(III) μ-Hydroxo Bisporphyrins: Magneto–Structural Correlation and Effect of Metal Spin on Porphyrin Core Deformation. Inorg Chem 2016; 55:3239-51. [DOI: 10.1021/acs.inorgchem.5b02226] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Debangsu Sil
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Susovan Bhowmik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | | | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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45
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Dey S, Sil D, Pandit YA, Rath SP. Effect of Two Interacting Rings in Metalloporphyrin Dimers upon Stepwise Oxidations. Inorg Chem 2016; 55:3229-38. [DOI: 10.1021/acs.inorgchem.5b02065] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Soumyajit Dey
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Debangsu Sil
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Younis Ahmad Pandit
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
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46
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Mondal P, Rath SP. Cyclic Zinc(II) Bisporphyrin-Based Molecular Switches: Supramolecular Control of Complexation-Mediated Conformational Switching and Photoinduced Electron Transfer. Chemistry 2016; 22:5607-19. [DOI: 10.1002/chem.201504829] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 01/17/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Pritam Mondal
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
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