1
|
Kalaiselvan A, Naniyil A, Ipe RM, Krishna Isukapalli SV, Vennapusa SR, Andrews AP, Gokulnath S. Stable Inner 2H Tautomer of N-Confused-like Porphyrin Embedded with a Carbazole Subunit: Synthesis, Metal Coordination, and Magnetic and Anion Sensing Studies. J Org Chem 2023; 88:14377-14387. [PMID: 37787478 DOI: 10.1021/acs.joc.3c01255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
A new class of N-confused porphyrin 1 embedded with a carbazole subunit was prepared via [3 + 1] acid-catalyzed condensation of appropriate precursors. 1 underwent smooth metal complexation with Pd(II) and Cu(II) salts to provide the corresponding diamagnetic 1-Pd and paramagnetic 1-Cu, respectively. The single-crystal X-ray structure of 1-Pd is evident with a square-planar Pd-center through C-H activation of inverted pyrrole. Superconducting quantum interference device analysis combined with electron paramagnetic resonance (EPR) results provided insights into the paramagnetic nature of 1-Cu. Further, a ratiometric enhancement of near-IR fluorescence at 746 nm was found to be reversible upon adding CN- and F- ions. The solid-state structure of 1-Pd confirms that the anionic species is due to NH deprotonation.
Collapse
Affiliation(s)
- Arumugam Kalaiselvan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Athira Naniyil
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Ruth Mariam Ipe
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Sai Vamsi Krishna Isukapalli
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Sivaranjana Reddy Vennapusa
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Alex P Andrews
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Sabapathi Gokulnath
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| |
Collapse
|
2
|
Ipe RM, Parammal A, Nag P, Mori S, Vennapusa SR, Gokulnath S. Synthetic Model for FRET Constructed from Covalently Linked Porphyrin Dimers through a Pyrene Bridge. J Org Chem 2023; 88:5780-5790. [PMID: 37025003 DOI: 10.1021/acs.joc.3c00229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
We report the synthesis and characterization of two porphyrin arrays C6F5-PyZnDP and Mes-PyZnDP covalently linked by a pyrene moiety which differs from their substituents at their meso-positions. The key precursor bis-dipyrromethane linked with a pyrene bridge was prepared by the acid-catalyzed condensation of pyrene-1,6-dialdehyde with excess pyrrole. The synthesis of C6F5-PyZnDP was carried out via two different synthetic routes, with one being efficient over the other. Therefore, the superior route was employed for the synthesis of C6F5-PyZnDP and Mes-PyZnDP. Both the free base and metalated diporphyrins show bathochromically shifted absorption and intense red emission due to the extended π-conjugation through pyrene and porphyrins. The single-crystal X-ray structure reveals an orthogonal orientation of pyrene in between the two planar porphyrins and a slipped stacked packing arrangement in the crystal structure with large meso-meso distances. DFT analysis of both the ground state and the excited S1 state of the macrocycles indicates the difference in the HOMO and LUMO contribution in both the states arising from slight twisting from the mean orthogonal position in the excited state. Further, the Förster energy transfer (FRET) efficiencies from pyrene (donor) to the covalently linked Zn-porphyrins (acceptor) are estimated to be 85 and 91% for Mes-PyZnDP and C6F5-PyZnDP, respectively.
Collapse
Affiliation(s)
- Ruth Mariam Ipe
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura 695-551, Kerala, India
| | - Athira Parammal
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura 695-551, Kerala, India
| | - Probal Nag
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura 695-551, Kerala, India
| | - Shigeki Mori
- Division of Material Science, Advanced Research Support Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577, Ehime, Japan
| | - Sivaranjana Reddy Vennapusa
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura 695-551, Kerala, India
| | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura 695-551, Kerala, India
| |
Collapse
|
3
|
Edwin A, Sulfikarali T, Kuppadakkath G, Gokulnath S. Unprecedented formation of azulicorroles from the scrambling of azulitripyrrane. J PORPHYR PHTHALOCYA 2022. [DOI: 10.1142/s1088424622500808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
4
|
Ipe RM, Nag P, Mori S, Nambiar AP, Vennapusa SR, Gokulnath S. Synthesis, Structure, and Optical Properties of a Bis-Macrocycle Derived from a Highly Emissive 1,3,6,8-Tetra(1 H-pyrrol-2-yl)pyrene. J Org Chem 2022; 87:15022-15030. [PMID: 36321998 DOI: 10.1021/acs.joc.2c01362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A tetra-functionalized pyrene precursor 4b is prepared using the Suzuki-Miyaura coupling of 1,3,6,8-tetrabromopyrene with N-Boc-2-pyrroleboronic acid. 4b displayed a blue emission with a high quantum yield (ϕF = 0.89). 4b is subjected to [3 + 2] Lewis acid-catalyzed condensation with 2,2'-bithiophene-dialcohol 5, affording a planar bis-N2S2 internally linked with pyrene. The single-crystal X-ray structure of bis-N2S2 revealed a planar conformation with all of the pyrrolic nitrogens and thiophenic sulfurs pointing toward the macrocyclic core. Further, the reduction of bis-N2S2 was attempted in the presence of Zn/NH4Cl at room temperature in CHCl3. A sharp color change from pink to brown was observed presumably due to the formation of its reduced congener bis-N2S2-2H. However, the reduced species was found to revert back to its oxidized form over a period of 25 min in CHCl3. Density functional theory (DFT) studies reveal that the two monocyclic halves of bis-N2S2-2H exhibit differences in aromaticity depending on amino and imino pyrroles present inside each individual core. Such a conversion was also monitored by ultraviolet-visible (UV-vis) absorption spectral studies, and the exact composition of bis-N2S2-2H was confirmed by High-resolution/mass spectrometry (HR/MS) analysis. Experimental and theoretical studies reveal a weak aromatic character of bis-N2S2 due to the absence of global conjugation.
Collapse
Affiliation(s)
- Ruth Mariam Ipe
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695-551, India
| | - Probal Nag
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695-551, India
| | - Shigeki Mori
- Division of Material Science, Advanced Research Support Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | - Anjana P Nambiar
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695-551, India
| | - Sivaranjana Reddy Vennapusa
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695-551, India
| | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, Kerala 695-551, India
| |
Collapse
|
5
|
Moorthy M, Karnan M, Suresh Balaji S, Gokulnath S, Sathish M. Nanoarchitectonics with Beetroot Peel Waste Derived Activated Carbon for Improved Electrochemical Performances in Supercapacitors using Redox Additive Electrolyte. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
6
|
Ajay J, Sulfikarali T, George SM, Gokulnath S. Conformationally Distinct [26]Heterorubyrin(1.1.0.1.1.0) Macrocycles and Their Bis-BODIPYs: Synthesis, Structure, and Optical Properties. Org Lett 2022; 24:1000-1004. [PMID: 35030002 DOI: 10.1021/acs.orglett.1c04043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two conformationally different [26]rubyrin(1.1.0.1.1.0) macrocycles with varying heteroatoms (S/O) and their bis-BODIPYs are reported. The solid-state structure confirms O2N4 with fairly planar pyrrole-inverted conformation, whereas a thiophene-inverted structure for S2N4 is observed. Such conformational differences can also be clearly realized from their spectral and optical features. Upon BF2 complexation, both rubyrins led to their respective bis-BODIPYs where S2N4-BOD displayed a perfectly planar conformation as evident from its X-ray structure.
Collapse
Affiliation(s)
- Jayaprakash Ajay
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | - Thondikkal Sulfikarali
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | - Sandra Mariya George
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| |
Collapse
|
7
|
Sulfikarali T, Behera G, Ajay J, Mori S, Kakarlamudi AC, Vennapusa SR, Gokulnath S. Disruption of Antiaromaticity in Structurally Related Expanded Porphyrin-like Macrocycles with Benzene Linkers. Org Lett 2021; 24:245-249. [PMID: 34928164 DOI: 10.1021/acs.orglett.1c03903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1,4-Phenylene-linked cyclotrimer (3T) and cyclotetramer (4T) have been synthesized via Lewis acid-catalyzed self-condensation of appropriate precursors. Structural and Density Functional Theory (DFT) studies reveal the disruption of annulenic conjugation in both 3T and 4T by linking phenylene rings prevented them from global antiaromaticity. The single crystal X-ray structure of 4T reveals all the nitrogens are pointing toward the macrocyclic core with near-planar and square-shaped geometry, thus in sharp contrast to the ring-strained conformation of 3T.
Collapse
Affiliation(s)
- Thondikkal Sulfikarali
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695 016, India
| | - Govind Behera
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695 016, India
| | - Jayaprakash Ajay
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695 016, India
| | - Shigeki Mori
- Division of Material Science, Advanced Research Support Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan
| | | | | | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695 016, India
| |
Collapse
|
8
|
Kalaiselvan A, Dhamija S, Aswathi C, De AK, Gokulnath S. Planar hexaphyrin-like macrocycles turning into bis-BODIPYs with box-shaped structures exhibiting excitonic coupling. Chem Commun (Camb) 2021; 57:11485-11488. [PMID: 34651622 DOI: 10.1039/d1cc04403f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Planar carbazole based hexaphyrin-like macrocycles with bis-coordinating cores and box-shaped cyclic BODIPYs were synthesized. Solution and solid-state structure analysis of the free macrocycles indicates an inversion of two pyrrole rings, resulting in a two-dipyrrin-like environment. The BF2 complexes show large Stokes shifts and exhibit excitonic coupling, fine-tuned by the meso-substituents.
Collapse
Affiliation(s)
- Arumugam Kalaiselvan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| | - Shaina Dhamija
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Punjab-140306, India.
| | - Chakrapani Aswathi
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| | - Arijit K De
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Punjab-140306, India.
| | - Sabapathi Gokulnath
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| |
Collapse
|
9
|
Ajay J, Sandra GM, Ishida M, Sulfikarali T, Gokulnath S. Lewis acid-catalyzed formation of triply S-confused hexaphyrin (1.0.1.0.1.0) and its structure-property correlations. J PORPHYR PHTHALOCYA 2021. [DOI: 10.1142/s108842462150108x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A simple rigid precursor termed as a “diheterole” bearing thiophene linked to [Formula: see text]-pyrrole at 4-position was prepared using a three-step synthetic strategy. This functionalized diheterole was allowed to undergo acid-catalyzed condensation in the presence of Lewis acid (BF3 [Formula: see text] Et2O) to produce the [2+2+2] cyclotrimer 1 as a major product with trace formation of 2and higher homologues.Various 1D and 2D NMR analyses along with theoretical investigations indicate that the molecule 1 exhibits nonaromaticity due to its non-conjugated annulenic structure. The optical properties and electronic structures were analyzed using UV-vis absorption spectroscopy and time-dependent density functional theory calculations. Detailed structural analyses revealed that the conformationally rigid triply S-confused hexaphyrin 1 adopts nearly planar geometry with three thiophene rings inverted. Upon protonation, the individual rings are tilted largely due to the steric congestion by both [Formula: see text]-CH’s and pyrrolic NH’s inside the core. The calculated NICS(0) values of +1.73 ppm for the protonated species, 1 [Formula: see text] 3H[Formula: see text] indicates the distinct non-aromatic feature as observed in 1 (NICS value of +2.34 ppm).
Collapse
Affiliation(s)
- Jayaprakash Ajay
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695551, India
| | - George Mariya Sandra
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695551, India
| | - Masatoshi Ishida
- Department of Applied Chemistry, Graduate School of Engineering and Center for Molecular Systems, Kyushu University, Fukuoka 819-0395, Japan
| | - Thondikkal Sulfikarali
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695551, India
| | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695551, India
| |
Collapse
|
10
|
Kalaiselvan A, Spergen A, Krishna ISV, Reddy VS, Gokulnath S. Double intramolecular hydrogen transfer assisted dual emission in a carbazole-embedded porphyrin-like macrocycle. Chem Commun (Camb) 2021; 57:4420-4423. [PMID: 33949463 DOI: 10.1039/d1cc00868d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The introduction of a pyrrole ring at one of the meso positions of carbazole-based porphyrins lowers the structural symmetry and results in dual emission, which strongly depends on the excitation wavelength and temperature. The origin of dual emission induced by NH-tautomerism is confirmed via photophysical and DFT calculations.
Collapse
Affiliation(s)
- Arumugan Kalaiselvan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| | - Aswini Spergen
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| | - Isukapalli Sai Vamsi Krishna
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| | - Vennapusa Sivaranjana Reddy
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| | - Sabapathi Gokulnath
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram-695551, Maruthamala P.O., Vithura, Kerala, India.
| |
Collapse
|
11
|
Ajay J, Sulfikarali T, Chakravarthy KA, Reddy VS, Gokulnath S. Hexathianonaphyrin(1.0.0.1.0.0.1.0.0): Synthesis, optical, redox and protonation induced antiaromaticity. J PORPHYR PHTHALOCYA 2021. [DOI: 10.1142/s1088424621500322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A simple non-rigid precursor termed as a “triheterole” comprising of 2,2[Formula: see text]-bithiophene linked to [Formula: see text]-pyrrole was prepared using a four-step synthetic strategy. This functionalized triheterole was allowed to undergo acid catalyzed condensation in the presence of Lewis acid (BF3 [Formula: see text] Et2O) to produce the [3 + 3 + 3] cyclotrimer 1 as a major product with trace formation of its higher homologues. Electronic absorption spectrum of 1exhibited a characteristic band (520 nm) and broad band in the visible region. Upon protonation, significant bathochromic shift of the band (608 nm) and the broad band towards near-IR region (ca.1250 nm) indicates its antiaromatic (4[Formula: see text] conjugated circuit. Detailed structural analyses using temperature-dependent 1D and 2D NMR along with DFT level theoretical investigations indicate that the molecule exhibits weak antiaromaticity due to its large fluxional nature.
Collapse
Affiliation(s)
- Jayaprakash Ajay
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695551, India
| | - Thondikkal Sulfikarali
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695551, India
| | | | | | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695551, India
| |
Collapse
|
12
|
Yadav P, Awasthi A, Gokulnath S, Tiwari DK. DMSO as a Methine Source in TFA-Mediated One-Pot Tandem Regioselective Synthesis of 3-Substituted-1-Aryl-1H-Pyrazolo-[3,4-b]quinolines from Anilines and Pyrazolones. J Org Chem 2021; 86:2658-2666. [DOI: 10.1021/acs.joc.0c02696] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Pushpendra Yadav
- Molecular Synthesis and Drug Discovery Laboratory, Center of Biomedical Research (CBMR), Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
- Department of Chemistry, Institute of Science, Banaras Hindu University, 221005 Varanasi, Uttar Pradesh, India
| | - Annapurna Awasthi
- Molecular Synthesis and Drug Discovery Laboratory, Center of Biomedical Research (CBMR), Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
- Department of Chemistry, Institute of Science, Banaras Hindu University, 221005 Varanasi, Uttar Pradesh, India
| | - Sabapathi Gokulnath
- School of Chemistry, Indian Institute of Science Education and Research (IISER), Maruthamala P.O., Vithura, Thiruvananthapuram 695 551, Kerala, India
| | - Dharmendra Kumar Tiwari
- Molecular Synthesis and Drug Discovery Laboratory, Center of Biomedical Research (CBMR), Sanjay Gandhi Post-Graduate Institute of Medical Sciences Campus, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
| |
Collapse
|
13
|
Sulfikarali T, Ajay J, Suresh CH, Bijina PV, Gokulnath S. Synthesis, Structure, and Optical Properties of Di- m-benzihexaphyrins (1.1.0.0.0.0) and Di- m-benziheptaphyrins (1.0.1.0.0.0.0): Blackening of m-Phenylene-Linked Dicarbaporphyrinoids by Simple π-Expansion. J Org Chem 2020; 85:8021-8028. [PMID: 32390421 DOI: 10.1021/acs.joc.0c00754] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Acid-catalyzed condensation of a newly prepared di-m-benzipentapyrrane with appropriate mono- and diheterocyclic dialcohols selectively produced stable di-m-benzihexaphyrins and di-m-benziheptaphyrins with only two meso-carbon bridges. Single-crystal X-ray diffraction analyses reveal planar conformation with slight distortion of bridged phenylene rings. Despite the presence of m-phenylene units interrupting the global delocalization, the presence of bithiophene units in di-m-benziheptaphyrins 3a-b exhibits altered optical features covering the entire visible region (ca. 250-720 nm), exhibiting a black dye property as a "metal-free" porphyrinoid.
Collapse
Affiliation(s)
- Thondikkal Sulfikarali
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Jayaprakash Ajay
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Cherumuttathu H Suresh
- Inorganic and Theoretical Chemistry Section, Chemical Science and Technology Division, CSIR-National Institute of Interdisciplinary Science and Technology, Trivandrum, Kerala 695019, India
| | - Padinjare V Bijina
- Inorganic and Theoretical Chemistry Section, Chemical Science and Technology Division, CSIR-National Institute of Interdisciplinary Science and Technology, Trivandrum, Kerala 695019, India
| | - Sabapathi Gokulnath
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| |
Collapse
|
14
|
Kalaiselvan A, Vamsi Krishna IS, Nambiar AP, Edwin A, Reddy VS, Gokulnath S. Carbazole-Based Porphyrins: Synthesis, Structure–Photophysical Property Correlations, and Mercury Ion Sensing. Org Lett 2020; 22:4494-4499. [DOI: 10.1021/acs.orglett.0c01500] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Arumugam Kalaiselvan
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | | | - Anjana Prasad Nambiar
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | - Aathira Edwin
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | | | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| |
Collapse
|
15
|
Wang Y, Kai H, Ishida M, Gokulnath S, Mori S, Murayama T, Muranaka A, Uchiyama M, Yasutake Y, Fukatsu S, Notsuka Y, Yamaoka Y, Hanafusa M, Yoshizawa M, Kim G, Kim D, Furuta H. Synthesis of a Black Dye with Absorption Capabilities Across the Visible-to-Near-Infrared Region: A MO-Mixing Approach via Heterometal Coordination of Expanded Porphyrinoid. J Am Chem Soc 2020; 142:6807-6813. [DOI: 10.1021/jacs.0c01824] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Yue Wang
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Hiroto Kai
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Masatoshi Ishida
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
| | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research (IISER), Thiruvananthapuram, Kerala 695581, India
| | - Shigeki Mori
- Advanced Research Support Center (ADRES), Ehime University, Matsuyama 790-8577, Japan
| | - Tomotaka Murayama
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Atsuya Muranaka
- Cluster for Pioneering Research (CPR), Advanced Elements Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Masanobu Uchiyama
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Cluster for Pioneering Research (CPR), Advanced Elements Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Yuhsuke Yasutake
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Susumu Fukatsu
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Yusuke Notsuka
- Graduate School of Advanced Health Sciences, Saga University, Saga 840-8502, Japan
| | - Yoshihisa Yamaoka
- Graduate School of Advanced Health Sciences, Saga University, Saga 840-8502, Japan
| | - Mamiko Hanafusa
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Michito Yoshizawa
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Gakhyun Kim
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Dongho Kim
- Department of Chemistry and Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Hiroyuki Furuta
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
| |
Collapse
|
16
|
Ajay J, Shirisha S, Ishida M, Ito K, Mori S, Furuta H, Gokulnath S. Planar Antiaromatic Core-Modified 24π Hexaphyrin(1.0.1.0.1.0) and 32π Octaphyrin(1.0.1.0.1.0.1.0) Bearing Alternate Hybrid Diheterole Units. Chemistry 2019; 25:2859-2867. [PMID: 30589136 DOI: 10.1002/chem.201805861] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Indexed: 11/09/2022]
Abstract
The Lewis acid catalyzed self-condensation of hybrid diheterole (furan-pyrrole and thiophene-pyrrole) precursors has afforded novel Hückel antiaromatic 24π hexaphyrin(1.0.1.0.1.0) and 32π octaphyrin(1.0.1.0.1.0.1.0) structures without β-annulated bridges. Single-crystal X-ray diffraction analysis of the hybrid porphyrinoids (S3 N3 -ox and O4 N4 -ox) revealed a nearly planar conformation and the 1 H NMR spectra suggest the presence of paratropic ring currents. These antiaromatic macrocycles show characteristic optical features and underwent reversible two-electron reduction to Hückel aromatic 26π- and 34π-electron species, respectively, as is evident from the results of spectroscopic and theoretical studies (nucleus-independent chemical shift (NICS) and anisotropy of the current-induced density (ACID) calculations). The incorporation of hybrid diheteroles alternately into expanded porphyrin skeletons provides a novel approach to the fine-tuning of the electronic structures of planar antiaromatic macrocycles.
Collapse
Affiliation(s)
- Jayaprakash Ajay
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, 695016, India
| | - Sriram Shirisha
- Inorganic & Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad, 500007, Telangana, India
| | - Masatoshi Ishida
- Department of Chemistry and Biochemistry, Graduate School of Engineering and Center for Molecular Systems, Kyushu University, Fukuoka, 819-0395, Japan
| | - Kosuke Ito
- Department of Chemistry and Biochemistry, Graduate School of Engineering and Center for Molecular Systems, Kyushu University, Fukuoka, 819-0395, Japan
| | - Shigeki Mori
- Advanced Research Support Center, Ehime University, Matsuyama, 790-8577, Japan
| | - Hiroyuki Furuta
- Department of Chemistry and Biochemistry, Graduate School of Engineering and Center for Molecular Systems, Kyushu University, Fukuoka, 819-0395, Japan
| | - Sabapathi Gokulnath
- Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, 695016, India
| |
Collapse
|
17
|
Borra S, Chandrasekhar D, Adhikary S, Rasala S, Gokulnath S, Maurya RA. Visible-Light Driven Photocascade Catalysis: Union of N,N-Dimethylanilines and α-Azidochalcones in Flow Microreactors. J Org Chem 2017; 82:2249-2256. [DOI: 10.1021/acs.joc.6b02932] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Satheesh Borra
- Applied Organic Chemistry Group, Chemical Science &Technology Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam 785006, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - D. Chandrasekhar
- Applied Organic Chemistry Group, Chemical Science &Technology Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam 785006, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - Susanta Adhikary
- Department
of Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
- Department
of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Kolkata 700032, India
| | - Sandeep Rasala
- Department
of Medicinal Chemistry and Pharmacology, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - Sabapathi Gokulnath
- School
of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram 695016, India
| | - Ram Awatar Maurya
- Applied Organic Chemistry Group, Chemical Science &Technology Division, CSIR-North East Institute of Science and Technology, Jorhat, Assam 785006, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| |
Collapse
|
18
|
Achary BS, Gokulnath S, Ghosh S, Mrinalini M, Prasanthkumar S, Giribabu L. Unprecedented Charge-Transfer Complex of Fused Diporphyrin as Near-Infrared Absorption-Induced High-Aspect-Ratio Nanorods. Chem Asian J 2016; 11:3498-3502. [PMID: 27781413 DOI: 10.1002/asia.201601363] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Indexed: 12/22/2022]
Abstract
Charge-transfer (CT) complexes of near-infrared absorbing systems have been unknown until now. Consequently, structural similarities between donor and acceptor are rather important to achieve this phenomenon. Herein, we report electron donors such as non-fused diporphyrin-anthracene (DP), zinc diporphyrin-anthracene (ZnDP) and fused zinc diporphyrin-anthracene (FZnDP) in which FZnDP absorbs in NIR region and permits a CT complex with the electron acceptor, perylene diimide (PDI) in CHCl3 exclusively. UV/Vis-NIR absorption, 1 H NMR, NOESY and powder X-ray diffraction analysis demonstrated that the CT complex formation occurs by π-π stacking between perylene units in FZnDP and PDI upon mixing together in a 1:1 molar concentration in CHCl3 , unlike non-fused ZnDP and DP. TEM and AFM images revealed that the CT complex initially forms nanospheres leading to nanorods by diffusion of CH3 OH vapors into the CHCl3 solution of FZnDP/PDI (1:1 molar ratio). Therefore, these CT nanorods could lead to significant advances in optical, biological and ferroelectric applications.
Collapse
Affiliation(s)
- B Shivaprasad Achary
- Inorganic & Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad-500007, Telangana, India
| | - Sabapathi Gokulnath
- School of Chemistry, Indian Institute of Scientific and Educational Research (IISER), Trivandrum-695016, Kerala, India
| | - Samrat Ghosh
- Photoscience&Photonics Division, CSIR-National Institute of Interdisciplinary Science and Technology (NIIST), Trivandrum-695019, Kerala, India
| | - Madoori Mrinalini
- Inorganic & Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad-500007, Telangana, India
| | - Seelam Prasanthkumar
- Inorganic & Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad-500007, Telangana, India
| | - Lingamallu Giribabu
- Inorganic & Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology (IICT), Tarnaka, Hyderabad-500007, Telangana, India.,Academy of Scientific and Innovation Research (AcSIR), New Delhi, India
| |
Collapse
|
19
|
Sudhakar K, Gokulnath S, Giribabu L, Lim GN, Trâm T, D'Souza F. Ultrafast Photoinduced Charge Separation Leading to High-Energy Radical Ion-Pairs in Directly Linked Corrole-C60and Triphenylamine-Corrole-C60Donor-Acceptor Conjugates. Chem Asian J 2015; 10:2708-19. [DOI: 10.1002/asia.201500679] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Indexed: 12/23/2022]
Affiliation(s)
- Kolanu Sudhakar
- Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology; Habsiguda Hyderabad 500007, Telangana India
| | - Sabapathi Gokulnath
- Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology; Habsiguda Hyderabad 500007, Telangana India
| | - Lingamallu Giribabu
- Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology; Habsiguda Hyderabad 500007, Telangana India
| | - Gary N. Lim
- Department of Chemistry; University of North Texas; 1155 Union Circle, #305070 Denton TX 76203-5017 USA
| | - Tạ Trâm
- Department of Chemistry; University of North Texas; 1155 Union Circle, #305070 Denton TX 76203-5017 USA
| | - Francis D'Souza
- Department of Chemistry; University of North Texas; 1155 Union Circle, #305070 Denton TX 76203-5017 USA
| |
Collapse
|
20
|
Gokulnath S, Achary BS, Kumar CK, Trivedi R, Sridhar B, Giribabu L. Synthesis, Structure and Photophysical Properties of Ferrocenyl or Mixed Sandwich Cobaltocenyl Ester Linkedmeso-Tetratolylporphyrin Dyads. Photochem Photobiol 2014; 91:33-41. [DOI: 10.1111/php.12372] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 10/16/2014] [Indexed: 01/21/2023]
Affiliation(s)
- Sabapathi Gokulnath
- Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology; Hyderbad India
| | | | - Chakka Kiran Kumar
- Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology; Hyderbad India
| | - Rajiv Trivedi
- Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology; Hyderbad India
| | - Balasubramanian Sridhar
- Laboratory of X-ray Crystallography; CSIR-Indian Institute of Chemical Technology; Hyderabad India
| | - Lingamallu Giribabu
- Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology; Hyderbad India
| |
Collapse
|
21
|
Gokulnath S, Nishimura K, Toganoh M, Mori S, Furuta H. Palladium-Induced Pyrrolic Rearrangement of a Singly to a Doubly N-Confused [26]Hexaphyrin. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201302955] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
22
|
Gokulnath S, Nishimura K, Toganoh M, Mori S, Furuta H. Palladium-Induced Pyrrolic Rearrangement of a Singly to a Doubly N-Confused [26]Hexaphyrin. Angew Chem Int Ed Engl 2013; 52:6940-3. [DOI: 10.1002/anie.201302955] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Indexed: 11/09/2022]
|
23
|
Toganoh M, Gokulnath S, Kawabe Y, Furuta H. Synthesis and Reactivity of 5,10,15-Triaryl Doubly N-Confused Bilanes. Chemistry 2012; 18:4380-91. [DOI: 10.1002/chem.201103034] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Indexed: 11/08/2022]
|
24
|
Gokulnath S, Toganoh M, Yamaguchi K, Mori S, Uno H, Furuta H. Confusion of Möbius aromaticity: disruption of annulenic pathway in singly N-confused [28]hexaphyrin and its mono-Pd(ii) complex. Dalton Trans 2012; 41:6283-90. [DOI: 10.1039/c2dt30306j] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
25
|
Gokulnath S, Yamaguchi K, Toganoh M, Mori S, Uno H, Furuta H. Singly N-Confused [26]Hexaphyrin: A Binucleating Porphyrinoid Ligand for Mixed Metals in Different Oxidation States. Angew Chem Int Ed Engl 2011; 50:2302-6. [DOI: 10.1002/anie.201006784] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 12/15/2010] [Indexed: 11/11/2022]
|
26
|
Chandrashekar TK, Prabhuraja V, Gokulnath S, Sabarinathan R, Srinivasan A. Fused core-modified meso-aryl expanded porphyrins. Chem Commun (Camb) 2010; 46:5915-7. [DOI: 10.1039/c000387e] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
27
|
Gokulnath S, Prabhuraja V, Suresh C, Chandrashekar T. Modified 26 and 28 π Hexaphyrins with Fivemeso-Links: Optical, Redox, and Structural Properties. Chem Asian J 2009; 4:861-869. [DOI: 10.1002/asia.200800397] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
28
|
Gokulnath S, Chandrashekar TK. Expanded porphyrins as third order non-linear optical materials: Some structure-function correlations. J CHEM SCI 2008. [DOI: 10.1007/s12039-008-0016-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
29
|
Affiliation(s)
- Sabapathi Gokulnath
- Department of Chemistry, Indian Institute of Technology, Kanpur-208016, India, and National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum, Kerala 695 019, India
| | - Tavarekere K. Chandrashekar
- Department of Chemistry, Indian Institute of Technology, Kanpur-208016, India, and National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum, Kerala 695 019, India
| |
Collapse
|
30
|
Abstract
Synthesis and reversible redox interconversion between core-modified [32]heptaphyrin (1.1.1.1.1.0.0) and [30]heptaphyrin (1.1.1.1.1.0.0) are reported.
Collapse
Affiliation(s)
- Sabapathi Gokulnath
- Department of Chemistry, Indian Institute of Technology, Kanpur-208016, India, and National Institute for Interdisciplinary Science and Technology, Trivandrum, Kerala 695019, India
| | | | | |
Collapse
|
31
|
Gokulnath S, Prabhuraja V, Sankar J, Chandrashekar TK. Smaragdyrin–Azobenzene Conjugates: Syntheses, Structure, and Spectral and Electrochemical Properties. European J Org Chem 2007. [DOI: 10.1002/ejoc.200600719] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
32
|
Sankar J, Rath H, Prabhuraja V, Gokulnath S, Chandrashekar TK, Purohit CS, Verma S. meso-meso-Linked Corrole Dimers with Modified Cores: Synthesis, Characterization, and Properties. Chemistry 2006; 13:105-14. [PMID: 16991181 DOI: 10.1002/chem.200600457] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The synthesis and characterization of the first examples of core-modified corrole dimers linked through the meso positions are described. The dimers are obtained by a simple Ag(I)- or Fe(III)-catalyzed coupling reaction in near-quantitative yields. The corroles obtained are metalated with metal ions, such as Cu(II) and Ni(II). The electronic-absorption spectral studies reveal weak electronic interaction between the two subunits and the exciton coupling observed for the free-base corrole dimer (1717 cm(-1)) is lower than that for the corresponding protonated derivative (4081 cm(-1)). The solution-state structure derived from (1)H and two-dimensional NMR spectral studies reveals a noncoplanar arrangement of two corrole units. Geometry optimization at the B3LYP-631G level also confirms the noncoplanar arrangement of corroles with a dihedral angle of 64.8 degrees between two corrole planes. The electron paramagnetic resonance (EPR) and magnetic characterization studies on the paramagnetic copper-metalated dimer indicate that both copper ions behave as independent spins without any noticeable interaction. Results of fluorescence studies reveal a bathochromic shift of about 60 nm upon dimerization. The first hyperpolarizability (beta) measured by using the hyper Rayleigh scattering (HRS) method reveals doubling of the beta values on progressing from monomer to dimer, attributed to enhanced pi conjugation. The use of copper dimers in the photocleavage of DNA is also explored. It is shown that the bimetallic copper dimer selectively cleaves the nucleic acids without affecting the proteins, suggesting a possible application of the copper complex in the removal of nucleic acid contaminants from protein extracts through a simple photolytic pathway.
Collapse
Affiliation(s)
- Jeyaraman Sankar
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
| | | | | | | | | | | | | |
Collapse
|