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New insights on the electronic, magnetic, electric and molecular structure of a bis-(4-cyanopyridine) iron(III) complex with the meso-tetrakis(4-methoxyphenyl)porphyrin. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.11.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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2
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Synthesis, Mössbauer, cyclic voltammetry, magnetic properties and molecular structures of the low-spin iron(III) bis(pyrazine) complexes with the para-fluoro and para-chloro substituted meso-tetraphenylporphyrin. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.02.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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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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4
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Liu Q, Tang M, Zeng W, Zhang X, Wang J, Zhou Z. Optimal Size Matching and Minimal Distortion Energy: Implications for Natural Selection by the Macrocycle of the Iron Species in Heme. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600883] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Qiuhua Liu
- College of Chemistry and Chemical EngineeringCentral South University410083ChangshaChina
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules of the Ministry of EducationSchool of Chemistry and Chemical EngineeringHunan University of Science and Technology411201XiangtanChina
| | - Min Tang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules of the Ministry of EducationSchool of Chemistry and Chemical EngineeringHunan University of Science and Technology411201XiangtanChina
| | - Wennan Zeng
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules of the Ministry of EducationSchool of Chemistry and Chemical EngineeringHunan University of Science and Technology411201XiangtanChina
| | - Xi Zhang
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules of the Ministry of EducationSchool of Chemistry and Chemical EngineeringHunan University of Science and Technology411201XiangtanChina
| | - Jianxiu Wang
- College of Chemistry and Chemical EngineeringCentral South University410083ChangshaChina
| | - Zaichun Zhou
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules of the Ministry of EducationSchool of Chemistry and Chemical EngineeringHunan University of Science and Technology411201XiangtanChina
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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
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6
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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
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Liu Q, Zhang X, Zeng W, Wang J, Zhou Z. Fine-Tuning of Electronic Structure of Cobalt(II) Ion in Nonplanar Porphyrins and Tracking of a Cross-Hybrid Stage: Implications for the Distortion of Natural Tetrapyrrole Macrocycles. J Phys Chem B 2015; 119:14102-10. [DOI: 10.1021/acs.jpcb.5b08431] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Qiuhua Liu
- College
of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China
- Key
Laboratory of Theoretical Organic Chemistry and Functional Molecule
of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Xi Zhang
- Key
Laboratory of Theoretical Organic Chemistry and Functional Molecule
of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Wennan Zeng
- Key
Laboratory of Theoretical Organic Chemistry and Functional Molecule
of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Jianxiu Wang
- College
of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China
| | - Zaichun Zhou
- Key
Laboratory of Theoretical Organic Chemistry and Functional Molecule
of the Ministry of Education; School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
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8
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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
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9
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Ikezaki A, Ono J, Ohgo Y, Fukagawa M, Ikeue T, Nakamura M. Electronic structure of low-spin six-coordinate iron(III) meso-tetrapropylchlorin complexes. J PORPHYR PHTHALOCYA 2014. [DOI: 10.1142/s1088424614500576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Low-spin iron(III) tetrapropylchlorins [ Fe ( T n PrC ) L 2]± (L = HIm, 1-MeIm, DMAP, CN-, 4-CNPy, tBuNC) adopt the dxy-type ground state regardless of the nature of axial ligands. Among the complexes examined, [ Fe ( T n PrC )( t BuNC )2]+ has shown quite unique spectroscopic properties as described below. (1) 1 H NMR signals were extremely broad as compared with those of other complexes. In particular, 5,20- CH 2(α) signal was too broad to detect. (2) No signals except C γ were observed in 13 C NMR spectra. (3) Tetragonal splitting parameter (|Δ|) estimated by the EPR g values at 4.2 K reached as much as 12.4 λ, which is the largest |Δ| value among all the low-spin iron(III) porphyrins and porphyrinoids reported previously. On the basis of these results, we have concluded that [ Fe ( T n PrC )( t BuNC )2]+ adopts the low-spin iron(III) with (dxz, dyz)4(dxy)1 electronic ground state at 4.2–30 K where the EPR spectra are taken, while it should be expressed as the low-spin Fe ( II ) chlorin π-radical cation [ Fe II ( T n PrC .)( t BuNC )2]+ at ambient temperature where the NMR spectra are taken.
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Affiliation(s)
- Akira Ikezaki
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
| | - Jyunpei Ono
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
| | - Yoshiki Ohgo
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
| | - Mari Fukagawa
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
| | - Takahisa Ikeue
- Department of Material Science, Interdisciplinary Faculty of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
| | - Mikio Nakamura
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
- Department of Chemistry, Faculty of Science, Toho University, Funabashi 274-8510, Japan
- Research Center for Materials with Integrated Properties, Toho University, Funabashi 274-8510, Japan
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Wesełucha-Birczyńska A, Kozicki M, Czepiel J, Łabanowska M, Nowak P, Kowalczyk G, Kurdziel M, Birczyńska M, Biesiada G, Mach T, Garlicki A. Human erythrocytes analyzed by generalized 2D Raman correlation spectroscopy. J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2014.03.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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11
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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]
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12
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Barbee J, Kuznetsov AE. Revealing substituent effects on the electronic structure and planarity of Ni-porphyrins. COMPUT THEOR CHEM 2012; 981:73-85. [PMID: 23560251 DOI: 10.1016/j.comptc.2011.11.049] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Using density functional theory, we have studied the effects on structural and electronic consequences (including HOMO-LUMO energy gaps, vertical ionization potentials (IPv), and vertical electron affinities (EAv)) of the following two factors: (a) meso- and β-substituents acting as inductive donors (CH3), inductive acceptors that are electron-donating through resonance (Br), inductive electron acceptors (CF3), and resonance enabled acceptors (NO2); and (b) complete replacement of pyrrole nitrogens with P-atoms. The principal results of the study are: (1) For the bare Ni-porphyrin, the solvents were found not to affect the HOMO-LUMO gaps but to change the IPv and EAv noticeably. (2) In the series CH3 → Br → CF3 → NO2 the HOMO-LUMO energy gaps, IPv, and EAv increase for both meso- and β-substituents. The ruffling distortion of the porphyrin core is retained, and becomes stronger for the two acceptor groups. In general, effects of meso-substituents on the ruffling distortion of the porphyrin core is more pronounced. (3) Most significantly, complete replacement of pyrrole nitrogens in the NiP with phosphorus atoms produces the species, NiP(P)4, with the structural and electronic features drastically different from the original NiP. This implies that NiP(P)4 can possess interesting and unusual novel properties, including aromaticity and reactivity, leading to its various beneficial potential applications. Furthermore, NiP(P)4 high stability both in the gas phase and different solvents was shown, implying the feasibility of its synthesis.
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Affiliation(s)
- Jenna Barbee
- Department of Chemistry, Duke University, Durham, NC 27708, USA
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Ikeue T, Kurahashi S, Handa M, Sugimori T, Nakamura M. Electronic structure of five- and six-coordinate iron(III) tetraazaporphyrin complexes: pyrrole-Cαchemical shift as a useful probe. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s1088424608000418] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Electronic structure of a series of five-coordinate Fe ( OArTAzP ) X ( OAr = octaaryltetraazaporphyrin , X = Cl-, Br-, I-; Ar = 4-tert-butylphenyl) have been examined on the basis of1H NMR,13C NMR, and EPR spectroscopy as well as SQUID magnetometry. These complexes adopt the intermediate-spin state as in the case of analogous complexes reported by Fitzgerald et al. (Inorg. Chem. 1992; 31: 2006-2013) and Stuzhin et al. (Inorg. Chim. Acta 1995; 236: 131-139). The13C NMR studies using13C -enriched complexes at the pyrrole α positions have revealed that the pyrrole- Cαsignals appear at extraordinary upfield positions, i.e. -130 to -250 ppm at 273 K, due to the dz2-a2 uand dπ-3 eginteractions. The Curie plots of the pyrrole- Cαsignals have further revealed that the iodide complex adopts a much purer intermediate-spin state than the bromide and chloride complexes. In contrast to the case of Fe ( OArTAzP ) X , six-coordinate [ Fe ( OArTAzP )( CN )2]-showed the pyrrole- Cαsignal at 47 ppm at 273 K, which indicates that the complex adopts the low-spin state with the ( dxy)2( dxz, dyz)3electron configuration. Thus, the13C NMR chemical shift of the pyrrole- Cαsignal turns out to be quite a good probe to elucidate the spin state and electron configuration of iron(III) tetraazaporphyrins, where the1H NMR spectroscopy is less useful because of the absence of the hydrogen atoms as well as the alkyl or aryl groups directly attached to the meso positions.
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Affiliation(s)
- Takahisa Ikeue
- Department of Chemistry, Faculty of Material Science, Shimane University, Matsue 690-8504, Japan
| | - Satoshi Kurahashi
- Department of Chemistry, Faculty of Material Science, Shimane University, Matsue 690-8504, Japan
| | - Makoto Handa
- Department of Chemistry, Faculty of Material Science, Shimane University, Matsue 690-8504, Japan
| | - Tamotu Sugimori
- Division of Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
| | - Mikio Nakamura
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
- Research Center for Materials with Integrated Properties, Toho University, Funabashi 274-8510, Japan
- Division of Chemistry, Graduate School of Science, Toho University, Funabashi 274-8510, Japan
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Niibori Y, Ikezaki A, Nakamura M. Methodology to determine the NMR chemical shifts of carbon atoms with radical character: A case of low-spin bis(tert-butylisocyanide) complex of (meso-tetrapropylporphyrinato)iron(III). INORG CHEM COMMUN 2011. [DOI: 10.1016/j.inoche.2011.05.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kouno S, Ikezaki A, Ikeue T, Nakamura M. Spin–spin interactions in iron(III) porphyrin radical cations with ruffled and saddled structure. J Inorg Biochem 2011; 105:718-21. [DOI: 10.1016/j.jinorgbio.2011.01.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 01/05/2011] [Accepted: 01/10/2011] [Indexed: 11/29/2022]
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Ikeue T, Handa M, Chamberlin A, Ghosh A, Ongayi O, Vicente MGH, Ikezaki A, Nakamura M. Benzoannelation Stabilizes the dxy1 State of Low-Spin Iron(III) Porphyrinates. Inorg Chem 2011; 50:3567-81. [DOI: 10.1021/ic1024873] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Takahisa Ikeue
- Department of Chemistry, Faculty of Material Science, Shimane University, 1060 Nishikawatsu-cho, Matsue-shi, Shimane 690-8504, Japan
| | - Makoto Handa
- Department of Chemistry, Faculty of Material Science, Shimane University, 1060 Nishikawatsu-cho, Matsue-shi, Shimane 690-8504, Japan
| | - Adam Chamberlin
- Department of Chemistry and the Center for Theoretical and Computational Chemistry, University of Tromso, Breivika, N-9037 Tromso, Norway
| | - Abhik Ghosh
- Department of Chemistry and the Center for Theoretical and Computational Chemistry, University of Tromso, Breivika, N-9037 Tromso, Norway
| | - Owendi Ongayi
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - M. Graça H. Vicente
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Akira Ikezaki
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
| | - Mikio Nakamura
- Department of Chemistry, School of Medicine, Toho University, Ota-ku, Tokyo 143-8540, Japan
- Division of Chemistry, Graduate School of Science, Toho University, Funabashi 274-8510, Japan
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Rajapandian V, Subramanian V. Calculations on the Structure and Spectral Properties of Cytochrome c551 Using DFT and ONIOM Methods. J Phys Chem A 2011; 115:2866-76. [DOI: 10.1021/jp110983v] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- V. Rajapandian
- Chemical Laboratory, Central Leather Research Institute, Council of Scientific and Industrial Research, Adyar, Chennai 600 020, India
| | - V. Subramanian
- Chemical Laboratory, Central Leather Research Institute, Council of Scientific and Industrial Research, Adyar, Chennai 600 020, India
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Tozuka A, Ohgo Y, Ikezaki A, Taniguchi M, Nakamura M. Electronic structure of highly ruffled low-spin iron(III) porphyrinates with electron withdrawing heptafluoropropyl groups at the meso positions. Inorg Chem 2010; 49:10400-8. [PMID: 20942414 DOI: 10.1021/ic101184y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bis(pyridine)[meso-tetrakis(heptafluoropropyl)porphyrinato]iron(III), [Fe(THFPrP)Py(2)](+), was reported to be the low-spin complex that adopts the purest (d(xz), d(yz))(4)(d(xy))(1) ground state where the energy gap between the iron d(xy) and d(π)(d(xz), d(yz)) orbitals is larger than the corresponding energy gaps of any other complexes reported previously (Moore, K. T.; Fletcher, J. T.; Therien, M. J. J. Am. Chem. Soc. 1999, 121, 5196-5209). Although the highly ruffled porphyrin core expected for this complex contributes to the stabilization of the (d(xz), d(yz))(4)(d(xy))(1) ground state, the strongly electron withdrawing C(3)F(7) groups at the meso positions should stabilize the (d(xy))(2)(d(xz), d(yz))(3) ground state. Thus, we have reexamined the electronic structure of [Fe(THFPrP)Py(2)](+) by means of (1)H NMR, (19)F NMR, and electron paramagnetic resonance (EPR) spectroscopy. The CD(2)Cl(2) solution of [Fe(THFPrP)Py(2)](+) shows the pyrrole-H signal at -10.25 ppm (298 K) in (1)H NMR, the CF(2)(α) signal at -74.6 ppm (298 K) in (19)F NMR, and the large g(max) type signal at g = 3.16 (4.2 K) in the EPR. Thus, contrary to the previous report, the complex is unambiguously shown to adopt the (d(xy))(2)(d(xz), d(yz))(3) ground state. Comparison of the spectroscopic data of a series of [Fe(THFPrP)L(2)](+) with those of the corresponding meso-tetrapropylporphyrin complexes [Fe(TPrP)L(2)](+) with various axial ligands (L) has shown that the meso-C(3)F(7) groups stabilize the (d(xy))(2)(d(xz), d(yz))(3) ground state. Therefore, it is clear that the less common (d(xz), d(yz))(4)(d(xy))(1) ground state can be stabilized by the three major factors: (i) axial ligand with low-lying π* orbitals, (ii) ruffled porphyrin ring, and (iii) electron donating substituent at the meso position.
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Affiliation(s)
- Akira Tozuka
- Division of Chemistry, Graduate School of Science, Toho University, Funabashi 274-8510, Japan
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Patra R, Chaudhary A, Ghosh SK, Rath SP. Axial Ligand Orientations in a Distorted Porphyrin Macrocycle: Synthesis, Structure, and Properties of Low-Spin Bis(imidazole)iron(III) and Iron(II) Porphyrinates†Dedicated to Prof. Animesh Chakravorty on the occasion of his 75th birthday. Inorg Chem 2010; 49:2057-67. [DOI: 10.1021/ic9016504] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ranjan Patra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Arvind Chaudhary
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Sudip Kumar Ghosh
- 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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Patra R, Bhowmik S, Ghosh SK, Rath SP. Effects of axial pyridine coordination on a saddle-distorted porphyrin macrocycle: stabilization of hexa-coordinated high-spin Fe(iii) and air-stable low-spin iron(ii) porphyrinates. Dalton Trans 2010; 39:5795-806. [DOI: 10.1039/b924742d] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ikezaki A, Ohgo Y, Nakamura M. NMR studies on the electronic structure of one-electron oxidized complexes of iron(III) porphyrinates. Coord Chem Rev 2009. [DOI: 10.1016/j.ccr.2009.01.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ikezaki A, Takahashi M, Nakamura M. Models for Cytochromes c′: Observation of an Extremely Labile Spin State in Monoimidazole Complexes of Saddle-Shaped Iron(III) Porphyrinates. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200902224] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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23
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Ikezaki A, Takahashi M, Nakamura M. Models for Cytochromes c′: Observation of an Extremely Labile Spin State in Monoimidazole Complexes of Saddle-Shaped Iron(III) Porphyrinates. Angew Chem Int Ed Engl 2009; 48:6300-3. [DOI: 10.1002/anie.200902224] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Patra R, Rath SP. Cyanide binding to iron in a highly distorted porphyrin macrocycle: Synthesis and structure of low-spin Fe(II) dicyano porphyrin. INORG CHEM COMMUN 2009. [DOI: 10.1016/j.inoche.2009.04.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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The Effect of Steric Crowding on Porphyrin Conformation and Ring Orientations in a Series of Iron(III) μ-Oxo Dimers Containingmeso-Nitrooctaethylporphyrins. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200800799] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Ghosh SK, Patra R, Rath SP. Axial ligand coordination in sterically strained vanadyl porphyrins: synthesis, structure, and properties. Inorg Chem 2008; 47:9848-56. [PMID: 18823111 DOI: 10.1021/ic800714w] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A hitherto unknown family of six-coordinate vanadyl porphyrins of the sterically crowded, nonplanar 2,3,7,8,12,13,17,18-octaethyl-5,10,15,20-tetranitroporphyrin incorporating axial ligand L [where L is pyridine, tetrahydrofuran (THF), or methanol (MeOH)] has been isolated as VO(tn-OEP)(L) in the solid phase for the first time and also structurally characterized. The presence of four electron-withdrawing, bulky nitro groups at the meso positions of vanadyl octaethylporphyrins severely distorts the porphyrin macrocycles and significantly enhances the affinity for the axial ligands, where even weak sigma-donating ligands, such as MeOH, bind strongly enough to be isolable in the solid phase and that too under the offset effects of the macrocyclic distortions. Thus, the axial ligand affinity is influenced by both the electronic and conformational effect, which cannot be separated completely in this series. The solid-state magnetic measurements and their typical electron paramagnetic resonance (EPR) spectrum show the presence of a single, unpaired electron, consistent with V(IV) formulation. The VO stretching frequency for VO(tn-OEP) occurs as a sharp, strong peak at 1008 cm(-1), which is consistent with five-coordinate vanadyl porphyrins, while VO(tn-OEP)(L) displays a strong band at lower wavenumbers. The downshift in nu(VO) upon axial coordination increases with increasing donor strength of the axial ligands; for pyridine, the downshift is 30 cm(-1), while for THF and MeOH, the downshifts are nearly 18 cm(-1). X-ray structure determinations authenticate axial coordination in a purely saddle-distorted porphyrin macrocycle for all of the complexes reported here in which V-Np distances are significantly shorter, while the porphyrin cores have been expanded on axial ligand coordination. As a result, vanadium atoms are more inplane than in a five-coordinate species. The binding of L does not change the spin or metal oxidation states (V(IV), d(1)-system) of the complexes; therefore, the changes observed are truly the reflections of axial ligand coordination. Electrochemical data obtained from cyclic voltammetric studies reveal that the complexes are much easier to reduce (by approximately 1200 mV) but more difficult to oxidize (by approximately 500 mV) as compared to nearly planar VO(OEP). The complexes undergo two one-electron oxidations due to pi-cation radical and dication formation and three one-electron reductions. The first two reductions are because of pi-anion radical and dianion formation, while the third quasi-reversible reduction is assigned to a metal-centered process (V(IV) --> V(III)). These results can be useful for identifying the interaction of the vanadyl porphyrins with the biological targets in their reported involvement in potent insulinomimetic activity and in anti-HIV agents.
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Affiliation(s)
- Sudip Kumar Ghosh
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
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Patra R, Chaudhary A, Ghosh SK, Rath SP. Modulation of Metal Displacements in a Saddle Distorted Macrocycle: Synthesis, Structure, and Properties of High-Spin Fe(III) Porphyrins and Implications for the Hemoproteins. Inorg Chem 2008; 47:8324-35. [DOI: 10.1021/ic800944q] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Ranjan Patra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Arvind Chaudhary
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India
| | - Sudip Kumar Ghosh
- 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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Eguchi H, Ohgo Y, Ikezaki A, Neya S, Nakamura M. Bis(1-methylimidazole) Complex of Iron(III) Oxypyriporphyrin Adopting an Intermediate-spin State. CHEM LETT 2008. [DOI: 10.1246/cl.2008.768] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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