1
|
Sarkar S, Shah Tuglak Khan F, Guchhait T, Rath SP. Binuclear complexes with single M-F-M bridge (M: Fe, Mn, and Cu): A critical analysis of the impact of fluoride for isoelectronic hydroxide substitution. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.215003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
2
|
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]
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
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
| |
Collapse
|
5
|
Li M, Scheidt WR. The Simplest Iron μ-oxo Species. The Molecular Structure of {[Fe(porphine)]2O}. J PORPHYR PHTHALOCYA 2020. [DOI: 10.1142/s108842462050025x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We have prepared a new [Formula: see text]-oxo iron(III) porphyrin complex based on the simplest possible porphyrin ligand, porphine. Our structure determination for {[Fe(porphine)]2O}shows that it has a decidedly different molecular structure compared to all other [Formula: see text]-oxo iron(III)porphyrin complexes with two independent porphyrin ligands. The Fe–O–Fe angle is 153.21 (16)[Formula: see text]which leads to a small interplanar angle of 22.7[Formula: see text]between the two porphine rings. This also leads to C[Formula: see text]C nonbonded contact as short as 3.35Å between the two rings. The twist angle of the two porphine rings is 16.8[Formula: see text]. Other structural features are in general accord with those expected for high-spin iron(III) porphyrinates.
Collapse
Affiliation(s)
- Ming Li
- Contribution from the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - W. Robert Scheidt
- Contribution from the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| |
Collapse
|
6
|
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
| |
Collapse
|
7
|
Carrasco MC, Hematian S. (Hydr)oxo-bridged heme complexes: From structure to reactivity. J PORPHYR PHTHALOCYA 2020. [DOI: 10.1142/s1088424619300258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Iron–porphyrins ([Formula: see text] hemes) are present throughout the biosphere and perform a wide range of functions, particularly those that involve complex multiple-electron redox processes. Some common heme enzymes involved in these processes include cytochrome P450, heme/copper oxidase or heme/non-heme diiron nitric oxide reductase. Consequently, the (hydr)oxo-bridged heme species have been studied for the important roles that they play in many life processes or for their application for catalysis and preparation of new functional materials. This review encompasses important synthetic, structural and reactivity aspects of the (hydr)oxo-bridged heme constructs that govern their function and application. The properties and reactivity of the bridging (hydr)oxo moieties are directly dictated by the coordination environment of the heme core, the nature and ligation of the second metal center attached to the (hydr)oxo group, the presence or absence of a linker, and the degree of flexibility around that linker within the scaffold. Here, we summarize the structural features of all known (hydr)oxo-bridged heme constructs and use those to categorize and thus, provide a more comprehensive picture of structure–function relationships.
Collapse
Affiliation(s)
- Maria C. Carrasco
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro 27402, USA
| | - Shabnam Hematian
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro 27402, USA
| |
Collapse
|
8
|
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]
|
9
|
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]
|
10
|
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
| |
Collapse
|
11
|
Abdullin D, Fleck N, Klein C, Brehm P, Spicher S, Lützen A, Grimme S, Schiemann O. Synthesis of μ
2
‐Oxo‐Bridged Iron(III) Tetraphenylporphyrin–Spacer–Nitroxide Dimers and their Structural and Dynamics Characterization by using EPR and MD Simulations. Chemistry 2019; 25:2586-2596. [DOI: 10.1002/chem.201805016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/13/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Dinar Abdullin
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| | - Nico Fleck
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| | - Christoph Klein
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
- Kekulé Institute of Organic Chemistry and Biochemistry Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Philipp Brehm
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| | - Sebastian Spicher
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstr. 4 53115 Bonn Germany
| | - Arne Lützen
- Kekulé Institute of Organic Chemistry and Biochemistry Gerhard-Domagk-Str. 1 53121 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical ChemistryUniversity of Bonn Beringstr. 4 53115 Bonn Germany
| | - Olav Schiemann
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| |
Collapse
|
12
|
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]
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
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.
Collapse
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
| |
Collapse
|
15
|
|
16
|
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
| |
Collapse
|
17
|
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]
|
18
|
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.
Collapse
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
| |
Collapse
|
19
|
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
| |
Collapse
|
20
|
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]
|
21
|
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.
Collapse
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
| |
Collapse
|
22
|
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.
Collapse
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.
| |
Collapse
|
23
|
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
| |
Collapse
|
24
|
Das A, Ghosh P, Priego JL, Jiménez-Aparicio R, Lahiri GK. Unsymmetric (μ-oxido)/(μ-pyrazolato) and Symmetric (μ-pyrazolato)2 Bridged Diosmium Frameworks: Electronic Structure and Magnetic Properties. Inorg Chem 2016; 55:8396-406. [DOI: 10.1021/acs.inorgchem.6b00898] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ankita Das
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Prabir Ghosh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - José Luis Priego
- Departamento de Química Inorgánica, Facultad
de Ciencias Químicas, Universidad Complutense, Ciudad Universitaria, E-28040 Madrid, Spain
| | - Reyes Jiménez-Aparicio
- Departamento de Química Inorgánica, Facultad
de Ciencias Químicas, Universidad Complutense, Ciudad Universitaria, E-28040 Madrid, Spain
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| |
Collapse
|
25
|
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
| |
Collapse
|
26
|
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
| |
Collapse
|
27
|
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
| |
Collapse
|
28
|
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
| |
Collapse
|
29
|
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
| |
Collapse
|
30
|
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
| |
Collapse
|
31
|
Dey S, Sil D, Rath SP. A Highly Oxidized Cobalt Porphyrin Dimer: Spin Coupling and Stabilization of the Four-Electron Oxidation Product. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201509430] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| |
Collapse
|
32
|
Dey S, Sil D, Rath SP. A Highly Oxidized Cobalt Porphyrin Dimer: Spin Coupling and Stabilization of the Four-Electron Oxidation Product. Angew Chem Int Ed Engl 2015; 55:996-1000. [DOI: 10.1002/anie.201509430] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Indexed: 11/10/2022]
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
| | - Sankar Prasad Rath
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur- 208016 India
| |
Collapse
|
33
|
Sil D, Dey S, Kumar A, Bhowmik S, Rath SP. Oxidation triggers extensive conjugation and unusual stabilization of two di-heme dication diradical intermediates: role of bridging group for electronic communication. Chem Sci 2015; 7:1212-1223. [PMID: 29910877 PMCID: PMC5975787 DOI: 10.1039/c5sc03120f] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/26/2015] [Indexed: 11/21/2022] Open
Abstract
Synthetic analogs of diheme enzyme MauG have been reported. Unlike the bis-Fe(iv) state in MauG, the 2e-oxidation stabilizes two ferric hemes, each coupled with a porphyrin π-cation radical.
MauG is a diheme enzyme that utilizes two covalently bound c-type hemes to catalyse the biosynthesis of the protein-derived cofactor tryptophan tryptophylquinone. The two hemes are physically separated by 14.5 Å and a hole-hopping mechanism is proposed in which a tryptophan residue located between the hemes undergoes reversible oxidation and reduction to increase the effective electronic coupling element and enhance the rate of reversible electron transfer between the hemes in bis-Fe(iv) MauG. The present work describes the structure and spectroscopic investigation of 2e-oxidations of the synthetic diheme analogs in which two heme centers are covalently connected through a conjugated ethylene bridge that leads to the stabilization of two unusual trans conformations (U and P′ forms) with different and distinct spectroscopic and geometric features. Unlike in MauG, where the two oxidizing equivalents are distributed within the diheme system giving rise to the bis-Fe(iv) redox state, the synthetic analog stabilizes two ferric hemes, each coupled with a porphyrin cation radical, a scenario resembling the binuclear dication diradical complex. Interestingly, charge resonance-transition phenomena are observed here both in 1e and 2e-oxidised species from the same system, which are also clearly distinguishable by their relative position and intensity. Detailed UV-vis-NIR, X-ray, Mössbauer, EPR and 1H NMR spectroscopic investigations as well as variable temperature magnetic studies have unraveled strong electronic communications between two porphyrin π-cation radicals through the bridging ethylene group. The extensive π-conjugation also allows antiferromagnetic coupling between iron(iii) centers and porphyrin radical spins of both rings. DFT calculations revealed extended π-conjugation and H-bonding interaction as the major factors in controlling the stability of the conformers.
Collapse
Affiliation(s)
- Debangsu Sil
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur-208016 , India . ;
| | - Soumyajit Dey
- Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur-208016 , India . ;
| | - Amit Kumar
- 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 . ;
| |
Collapse
|
34
|
Mondal P, Rath SP. Highly Selective and Sensitive Detection of Picric Acid Explosive by a Bisporphyrin Cleft: Synergistic Effects of Encapsulation, Efficient Electron Transfer, and Hydrogen Bonding. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201500645] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
35
|
Mondal P, Rath SP. Efficient Host-Guest Complexation of a Bisporphyrin Host with Electron Deficient Guests: Synthesis, Structure, and Photoinduced Electron Transfer. Isr J Chem 2015. [DOI: 10.1002/ijch.201500014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
36
|
Sainna MA, Sil D, Sahoo D, Martin B, Rath SP, Comba P, de Visser SP. Spin-State Ordering in Hydroxo-Bridged Diiron(III)bisporphyrin Complexes. Inorg Chem 2015; 54:1919-30. [DOI: 10.1021/ic502803b] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Mala A. Sainna
- Manchester Institute
of Biotechnology and School of Chemical Engineering and Analytical
Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Debangsu Sil
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Dipankar Sahoo
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Bodo Martin
- Anorganisch-Chemisches Institüt and Interdisciplinary
Center for Scientific Computing (IWR), University of Heidelberg, Im Neuenheimer
Feld 270, 69120 Heidelberg, Germany
| | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Peter Comba
- Anorganisch-Chemisches Institüt and Interdisciplinary
Center for Scientific Computing (IWR), University of Heidelberg, Im Neuenheimer
Feld 270, 69120 Heidelberg, Germany
| | - Sam P. de Visser
- Manchester Institute
of Biotechnology and School of Chemical Engineering and Analytical
Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| |
Collapse
|
37
|
Sahoo D, Rath SP. Controlled generation of highly saddled (porphyrinato)iron(iii) iodide, tri-iodide and one-electron oxidized complexes. Chem Commun (Camb) 2015; 51:16790-3. [DOI: 10.1039/c5cc07111a] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three iron(iii) porphyrinato complexes have been isolated selectively just by varying the iodine concentration, which eventually form the admixed-intermediate (iodo complex), pure intermediate (tri-iodide complex) and high-spin (1e-oxidized complex) states of iron where iodide and/or tri-iodide were used as axial ligands.
Collapse
Affiliation(s)
- Dipankar Sahoo
- 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
| |
Collapse
|
38
|
Fidalgo-Marijuan A, Barandika G, Bazán B, Urtiaga MK, Larrea ES, Iglesias M, Lezama L, Arriortua MI. Heterogeneous catalytic properties of unprecedented μ-O-[FeTCPP]2 dimers (H2TCPP = meso-tetra(4-carboxyphenyl)porphyrin): an unusual superhyperfine EPR structure. Dalton Trans 2015; 44:213-22. [DOI: 10.1039/c4dt02250e] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Solvent accessible volume of the active catalyst μ-O-[FeTCPP]2·nDMF dimer revealing an unusual superhyperfine EPR structure.
Collapse
Affiliation(s)
- Arkaitz Fidalgo-Marijuan
- Departamento de Mineralogía y Petrología
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- 48080 Bilbao
- Spain
| | - Gotzone Barandika
- Departamento de Química Inorgánica
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- 48080 Bilbao
- Spain
| | - Begoña Bazán
- Departamento de Mineralogía y Petrología
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- 48080 Bilbao
- Spain
| | - Miren Karmele Urtiaga
- Departamento de Mineralogía y Petrología
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- 48080 Bilbao
- Spain
| | - Edurne S. Larrea
- Departamento de Mineralogía y Petrología
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- 48080 Bilbao
- Spain
| | - Marta Iglesias
- Instituto de Ciencia de Materiales de Madrid-CSIC
- Sor Juana Inés de la Cruz 3
- 28049 Madrid
- Spain
| | - Luis Lezama
- Departamento de Química Inorgánica
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- 48080 Bilbao
- Spain
| | - María Isabel Arriortua
- Departamento de Mineralogía y Petrología
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- 48080 Bilbao
- Spain
| |
Collapse
|
39
|
Sil D, Rath SP. An ethane-bridged porphyrin dimer as a model of di-heme proteins: inorganic and bioinorganic perspectives and consequences of heme–heme interactions. Dalton Trans 2015; 44:16195-211. [DOI: 10.1039/c5dt00947b] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A brief account of our recent efforts on how inter-heme interactions can possibly change the structure and functional properties of the individual heme centers in a highly flexible ethane-bridged porphyrin dimer has been presented.
Collapse
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
| |
Collapse
|
40
|
Sil D, Khan FST, Rath SP. Axial Thiophenolate Coordination on Diiron(III)bisporphyrin: Influence of Heme–Heme Interactions on Structure, Function and Electrochemical Properties of the Individual Heme Center. Inorg Chem 2014; 53:11925-36. [DOI: 10.1021/ic5011677] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [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
| | | | - Sankar Prasad Rath
- Department of Chemistry, Indian Institute of Technology Kanpur
, Kanpur-208016, India
| |
Collapse
|
41
|
Kuter D, Streltsov V, Davydova N, Venter GA, Naidoo KJ, Egan TJ. Molecular structures and solvation of free monomeric and dimeric ferriheme in aqueous solution: insights from molecular dynamics simulations and extended X-ray absorption fine structure spectroscopy. Inorg Chem 2014; 53:10811-24. [PMID: 25275882 DOI: 10.1021/ic500454d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
CHARMM force field parameters have been developed to model nonprotein bound five-coordinate ferriheme (ferriprotoporphyrin IX) species in aqueous solution. Structures and solvation were determined from molecular dynamics (MD) simulations at 298 K of monomeric [HO-ferriheme](2-), [H2O-ferriheme](-), and [H2O-ferriheme](0); π-π dimeric [(HO-ferriheme)2](4-), [(H2O-ferriheme)(HO-ferriheme)](3-), [(H2O-ferriheme)2](2-), and [(H2O-ferriheme)2](0); and μ-oxo dimeric [μ-(ferriheme)2O](4-). Solvation of monomeric species predominated around the axial ligand, meso-hydrogen atoms of the porphyrin ring (Hmeso), and the unligated face. Existence of π-π ferriheme dimers in aqueous solution was supported by MD calculations where such dimers remained associated over the course of the simulation. Porphyrin rings were essentially coplanar. In these dimers major and minor solvation was observed around the axial ligand and Hmeso positions, respectively. In μ-oxo ferriheme, strong solvation of the unligated face and bridging oxide ligand was observed. The solution structure of the μ-oxo dimer was investigated using extended X-ray absorption fine structure (EXAFS) spectroscopy. The EXAFS spectrum obtained from frozen solution was markedly different from that recorded on dried μ-oxo ferriheme solid. Inclusion of five solvent molecules obtained from spatial distribution functions in the structure generated from MD simulation was required to produce acceptable fits to the EXAFS spectra of the dimer in solution, while the solid was suitably fitted using the crystal structure of μ-oxo ferriheme dimethyl ester which included no solvent molecules.
Collapse
Affiliation(s)
- David Kuter
- Scientific Computing Research Unit, †Department of Chemistry, University of Cape Town , Private Bag, Rondebosch 7701, South Africa
| | | | | | | | | | | |
Collapse
|
42
|
Silva AMN, Aguir A, Balula SS, Silva AMG, Rangel M. Characterization of a μ-oxo-bridged diiron porphyrin by ESI-LTQ-Orbitrap-MS. JOURNAL OF MASS SPECTROMETRY : JMS 2014; 49:763-765. [PMID: 25044905 DOI: 10.1002/jms.3405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 05/15/2014] [Accepted: 06/01/2014] [Indexed: 06/03/2023]
Affiliation(s)
- André M N Silva
- REQUIMTE/Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre s/n, 4169-007, Porto, Portugal
| | | | | | | | | |
Collapse
|
43
|
Rintoul L, Harper SR, Arnold DP. A systematic theoretical study of the electronic structures of porphyrin dimers: DFT and TD-DFT calculations on diporphyrins linked by ethane, ethene, ethyne, imine, and azo bridges. Phys Chem Chem Phys 2014; 15:18951-64. [PMID: 24097279 DOI: 10.1039/c3cp53396d] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Theoretical calculations of the geometries, electronic structures and electronic absorption spectra of a series of covalently-linked porphyrin dimers are reported. The diporphyrins comprise 5,10,15-triphenylporphyrinatozinc(II) (ZnTriPP) units linked through the meso carbons by two-atom bridges, namely 1,2-ethanediyl (1), trans-1,2-ethenediyl (2), ethynediyl (3), 1,2-iminomethenediyl (4), and transdiazenediyl (5). The structures were optimised in toluene solvent by Density Functional Theory (DFT), using the integral equation formalism variant of the polarizable continuum model. The calculations were performed using the B3LYP functional and the 6-31G(d,p) basis set. The complete molecules were modelled, with no substitution of smaller groups on the periphery. In parallel, the compounds 2–5 were prepared by known or novel synthetic routes, to enable comparisons of experimental electronic absorption spectra with those calculated using time dependent-DFT at the same level of theory. As the ethane dimer 1 is not yet synthetically accessible, the model monomer meso-2-phenylethylZnTriPP was used for comparisons with the theoretical predictions. The results form a self-consistent set, enabling for the first time legitimate comparisons of the electronic structures of the series, especially regarding the degree to which the porphyrin p-systems interact by conjugation across the bridges. The theoretical calculations of the electronic transitions match the observed spectra in toluene to a remarkable degree, especially with respect to the peak maximum of the Q band, which represents to a large degree the energy of the HOMO–LUMO transition. The imine 4 is intrinsically polar due to the asymmetric bridge, and the HOMO is located almost exclusively on the ZnTriPP unit attached to the nitrogen of the imine, and the LUMO on the C-attached ring. Thus the Q-band transition is mapped as a comprehensive charge-transfer from the former ring to the latter. This may have consequences for the non-linear optical properties of the system. The azoporphyrin 5 exhibits the largest splittings between the interacting MOs via the conjugated bridge, vindicating a prediction by Anderson and co-workers in 2002, and confirmed experimentally by our synthesis of 5. The collected results also indicate that this level of theory is more thanadequate as a model with which to handle these large delocalised molecules.
Collapse
Affiliation(s)
- Llew Rintoul
- School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, 4001, Australia.
| | | | | |
Collapse
|
44
|
Dey S, Rath SP. Syn–anti conformational switching in an ethane-bridged Co(ii)bisporphyrin induced by external stimuli: effects of inter-macrocyclic interactions, axial ligation and chemical and electrochemical oxidations. Dalton Trans 2014; 43:2301-14. [DOI: 10.1039/c3dt52784k] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
45
|
Ghosh SK, Bhowmik S, Sil D, Rath SP. Effect of Heme-Heme Interactions and Modulation of Metal Spins by Counter Anions in a Series of Diiron(III)-μ-hydroxo Bisporphyrins: Unusual Stabilization of Two Different Spins in a Single Molecular Framework. Chemistry 2013; 19:17846-59. [DOI: 10.1002/chem.201301318] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 08/16/2013] [Indexed: 11/10/2022]
|
46
|
Bhowmik S, Dey S, Sahoo D, Rath SP. Unusual Stabilization of an Intermediate Spin State of Iron upon the Axial Phenoxide Coordination of a Diiron(III)-Bisporphyrin: Effect of Heme-Heme Interactions. Chemistry 2013; 19:13732-44. [DOI: 10.1002/chem.201301242] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Indexed: 11/06/2022]
|
47
|
Kumar S, Vaidya S, Pissas M, Sanakis Y, Gupta R. Synthesis and Properties of Dinuclear μ‐Oxodiiron(III) Complexes of Amide‐Based Macrocyclic Ligands. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200683] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sushil Kumar
- Department of Chemistry, University of Delhi, Delhi 110007, India, Fax: +91‐11‐27666605, http://people.du.ac.in/~rgupta/
| | - Shefali Vaidya
- Department of Chemistry, University of Delhi, Delhi 110007, India, Fax: +91‐11‐27666605, http://people.du.ac.in/~rgupta/
| | - Michael Pissas
- Department of Materials Science, IAMPPNM, NCSR Demokritos, 15310 Ag. Paraskevi, Attiki, Greece
| | - Yiannis Sanakis
- Department of Materials Science, IAMPPNM, NCSR Demokritos, 15310 Ag. Paraskevi, Attiki, Greece
| | - Rajeev Gupta
- Department of Chemistry, University of Delhi, Delhi 110007, India, Fax: +91‐11‐27666605, http://people.du.ac.in/~rgupta/
| |
Collapse
|
48
|
Bhowmik S, Ghosh SK, Layek S, Verma HC, Rath SP. Protonation of an Oxo-Bridged Diiron Unit Gives Two Different Iron Centers: Synthesis and Structure of a New Class of Diiron(III)-μ-hydroxo Bisporphyrins and the Control of Spin States by Using Counterions. Chemistry 2012; 18:13025-37. [DOI: 10.1002/chem.201201466] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Indexed: 11/07/2022]
|
49
|
Axial phenoxide coordination on di-iron(III) bisporphyrin: Insights from experimental and DFT studies. J CHEM SCI 2011. [DOI: 10.1007/s12039-011-0156-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
|
50
|
Chaudhary A, Rath SP. Efficient Complexation of Pyrrole-Bridged Dizinc(II) Bisporphyrin with Fluorescent Probe Pyrene: Synthesis, Structure, and Photoinduced Singlet-Singlet Energy Transfer. Chemistry 2011; 17:11478-87. [DOI: 10.1002/chem.201101324] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Indexed: 11/11/2022]
|