1
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Deng YH, Sun TY, Wu YD. Understanding the Nonlinear Hammett Relationship in Osmylation of Olefins with OsO 4-Amine Ligands: Importance of Singlet-Diradical Character. J Org Chem 2024; 89:11173-11182. [PMID: 39072554 DOI: 10.1021/acs.joc.4c00693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Although the concerted [3 + 2] mechanism of osmium-catalyzed asymmetric dihydroxylation has been generally accepted, the unusual nonlinear Hammett relationship induced by amine-type ligands remains unexplained. To understand this, we carried out a density functional theory (DFT) study for the osmylation of substituted styrenes by the following: OsO4, OsO4-pyridine, OsO4-4-cyanopyridine, OsO4-4-pyrrolidinopyridine, and OsO4-quinuclidine. Calculations using the M06 functional successfully reproduce the experimentally observed nonlinear relationships. The transition states exhibit considerable singlet-diradical character, which causes the nonlinear Hammett relationship. Regardless of the presence or absence of an amine-type ligand, an electron donation from styrene to OsO4 is observed, indicating no mechanistic change. Calculations indicate that the electronic interaction between the amine-type ligand and styrene also influences the reaction rate.
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Affiliation(s)
- Yi-Hui Deng
- Key Laboratory of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Shenzhen Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, PR China
| | - Tian-Yu Sun
- Key Laboratory of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Shenzhen Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, PR China
- Institute of Chemical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Yun-Dong Wu
- Key Laboratory of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Shenzhen Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, PR China
- Institute of Chemical Biology, Shenzhen Bay Laboratory, Shenzhen 518132, China
- College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
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2
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Nevonen DE, Atoyebi AO, Luciano MP, Brückner C, Nemykin VN. Electronic Structures of an Annulated meso-Tetraphenylchlorin and a Related Chlorin Analogue Incorporating an 8-Membered Ring through MCD Spectroscopy and DFT Calculations. J Phys Chem A 2024; 128:4823-4829. [PMID: 38857383 DOI: 10.1021/acs.jpca.4c02803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
Herein, we compare the electronic structures of the metal-free and nickel(II) derivatives of an annulated meso-tetraphenyldihydroxychlorin with those of the (metallo)chlorin analogues derived by pyrroline β,β'-ring cleavage of the annulated (metallo)chlorins. These (metallo)chlorin analogues incorporate 8-membered heterocycles in place of the pyrroline, carry oxo-functionalities on the former pyrroline β-carbon atoms, and were previously shown to possess drastically ruffled (twisted) nonplanar conformations. The magnetic circular dichroism spectra of all chromophores investigated feature chlorin-like UV-vis spectra and correspondingly reversed (positive-to-negative in ascending energy) sign sequences in the Q-band region, indicative of ΔHOMO < ΔLUMO relationships. Density functional theory (DFT) calculations indicate that the HOMOs in all compounds are a1u-type molecular orbitals (in traditional for the porphyrin spectroscopy D4h point group). Time-dependent DFT calculations correlate well with the experimental spectra and indicate that Gouterman's four-orbital model can be applied to these chromophores. This work highlights to which degree synthetic chlorin analogues can deviate from the structural parameters of natural chlorins without losing their electronic chlorin characteristics.
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Affiliation(s)
- Dustin E Nevonen
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Adewole O Atoyebi
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Michael P Luciano
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Victor N Nemykin
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
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3
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Aicher D, Damunupola D, Stark CBW, Wiehe A, Brückner C. meso-Tetrahexyl-7,8-dihydroxychlorin and Its Conversion to ß-Modified Derivatives. Molecules 2024; 29:2144. [PMID: 38731635 PMCID: PMC11085094 DOI: 10.3390/molecules29092144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 04/30/2024] [Accepted: 05/01/2024] [Indexed: 05/13/2024] Open
Abstract
meso-Tetrahexylporphyrin was converted to its corresponding 7,8-dihydroxychlorin using an osmium tetroxide-mediated dihydroxylation strategy. Its diol moiety was shown to be able to undergo a number of subsequent oxidation reactions to form a chlorin dione and porpholactone, the first meso-alkylporphyrin-based porphyrinoid containing a non-pyrrolic building block. Further, the diol chlorin was shown to be susceptible to dehydration, forming the porphyrin enol that is in equilibrium with its keto-chlorin form. The meso-hexylchlorin dione could be reduced and it underwent mono- and bis-methylation reactions using methyl-Grignard reagents, and trifluoromethylation using the Ruppert-Prakash reagent. The optical and spectroscopic properties of the products are discussed and contrasted to their corresponding meso-aryl derivatives (where known). This contribution establishes meso-tetrahexyl-7,8-dihydroxychlorins as a new and versatile class of chlorins that is susceptible to a broad range of conversions to generate functionalized chlorins and a pyrrole-modified chlorin analogue.
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Affiliation(s)
- Daniel Aicher
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Dinusha Damunupola
- Department of Chemistry, University of Connecticut, 55 N Eagleville Rd., Storrs, CT 06269-3060, USA
| | - Christian B. W. Stark
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Arno Wiehe
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, 55 N Eagleville Rd., Storrs, CT 06269-3060, USA
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4
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Hewage N, Damunupola D, Zeller M, Brückner C. Direct Oxidations of meso-Tetrakis(pentafluorophenyl)porphyrin: Porphotrilactones and Entry into a Nonbiological Porphyrin Degradation Pathway. J Org Chem 2024; 89:6584-6589. [PMID: 38652047 DOI: 10.1021/acs.joc.4c00283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
The direct oxidations of meso-tetrakis(pentafluorophenyl)porphyrin using cetyltrimethylammonium permanganate (CTAP), RuCl3/Oxone/base or Ag+/oxalic acid each generate distinctive product mixtures that may contain, inter alia, porpho-mono-, di-, and trilactones. The CTAP and RuCl3/Oxone/base oxidations also generate a unique open chain tripyrrin derived from the degradation of a porpholactone oxazolone moiety. Thus, its formation and structure are distinctly different from all biological or nearly all other nonbiological biliverdin-like linear porphyrinoid degradation products that are derived from ring cleavages between the pyrrolic building blocks.
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Affiliation(s)
- Nisansala Hewage
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Dinusha Damunupola
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Matthias Zeller
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States
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5
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Bhattacharya S, Nevonen DE, Auty AJ, Graf A, Appleby M, Chaudhri N, Chekulaev D, Brückner C, Chauvet AAP, Nemykin VN. Photophysical Exploration of Two Isomers of Octaethyltrioxopyrrocorphin. J Phys Chem A 2023; 127:7694-7706. [PMID: 37690121 DOI: 10.1021/acs.jpca.3c03184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
The introduction of three β-oxosubstituents to octaethylporphyrin by means of an oxidation/rearrangement reaction generates the trioxopyrrocorphin chromophore. Pyrrocorphins (hexahydroporphyrins) are generally nonaromatic, but we recently demonstrated trioxopyrrocorphins to possess considerable aromatic character. This contribution explores the photophysical characteristics of these unusual chromophores. In agreement with density functional theory modeling, the UV-vis and magnetic circular dichroism spectra of the two─out of the four possible─triketone regioisomers investigated conform to the Gouterman model of porphyrinoid optical spectra, in alignment with their aromaticity. Their excited-state dynamics shed further light on the degree to which β-oxo substitutions tune the photophysical properties of porphyrinoids. Introduction of β-oxo functionalities increases the rate and yield of intersystem crossing and shortens the triplet state lifetime. Unexpectedly, the singlet oxygen generation yield of both pyrrocorphins remains relatively high, with modes of distortion from planarity likely enhancing triplet energy transfer. This work thus expands our understanding of a rare class of porphyrinoids and further characterizes them as sustaining aromatic porphyrinic π-systems. Our findings suggest triple β-oxo substitution as a viable route toward the development of novel, high-singlet oxygen yield porphyrinic photosensitizers.
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Affiliation(s)
- Sayantan Bhattacharya
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield S3 7HF, U.K
| | - Dustin E Nevonen
- Department of Chemistry, University of Tennessee, 1420 Circle Dr., Knoxville, Tennessee 37996-1600, United States
| | - Alexander J Auty
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield S3 7HF, U.K
| | - Arthur Graf
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield S3 7HF, U.K
| | - Martin Appleby
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield S3 7HF, U.K
| | - Nivedita Chaudhri
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Dimitri Chekulaev
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield S3 7HF, U.K
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Adrien A P Chauvet
- Department of Chemistry, University of Sheffield, Dainton Building, Sheffield S3 7HF, U.K
| | - Victor N Nemykin
- Department of Chemistry, University of Tennessee, 1420 Circle Dr., Knoxville, Tennessee 37996-1600, United States
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6
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Lalisse RF, Hadad CM, Brückner C, Guberman-Pfeffer MJ. [3 + 2]-Cycloadditions with Porphyrin β,β'-Bonds: Theoretical Basis of the Counterintuitive meso-Aryl Group Influence on the Rates of Reaction. J Org Chem 2022; 87:16473-16482. [PMID: 36444511 DOI: 10.1021/acs.joc.2c02192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Removal of a β,β'-bond from meso-tetraarylporphyrin using [3 + 2]-cycloadditions generates meso-tetraarylhydroporphyrins. Literature evidence indicates that meso-tetraphenylporphyrins react more sluggishly with 1,3-dipoles such as ylides and OsO4 (in the presence of pyridine) than meso-tetrakis(pentafluorophenyl)porphyrin. The trend is counterintuitive for the reaction with OsO4, as this formal oxidation reaction is expected to proceed more readily with more electron-rich substrates. This work presents a density functional theory-based computational study of the frontier molecular orbital (FMO) interactions and reaction profile thermodynamics involved in the reaction of archetypical cycloaddition reactions (a simple ylide, OsO4, OsO4·py, OsO4·(py)2, and ozone) with the β,β'-double bonds of variously fluorinated meso-arylporphyrins. The trend observed for the Type I cycloaddition of an ylide is straightforward, as lowering the LUMO of the porphyrin with increasing meso-phenyl-fluorination also lowers the reaction barrier. The corresponding simple FMO analyses of Type III cycloadditions do not correctly model the reaction energetics. This is because increasing fluorination leads to lowering of the porphyrin HOMO-2, thus increasing the reaction barrier. However, coordination of pyridine to OsO4 preorganizes the transition state complex; lowering of the energy barrier by the preorganization exceeds the increase in repulsive orbital interactions, overall accelerating the cycloaddition and rationalizing the counterintuitive experimental findings.
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Affiliation(s)
- Remy F Lalisse
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio 43210, United States
| | - Christopher M Hadad
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Avenue, Columbus, Ohio 43210, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Matthew J Guberman-Pfeffer
- Department of Molecular Biophysics and Biochemistry, Yale University, 333 Cedar St., New Haven, Connecticut 06510, United States.,Microbial Sciences Institute, Yale University, 840 West Campus Drive, West Haven, Connecticut 06516, United States
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7
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Hewage N, Guberman-Pfeffer MJ, Chaudhri N, Zeller M, Gascón JA, Brückner C. Syntheses and Aromaticity Parameters of Hexahydroxypyrrocorphin, Porphotrilactones, and Their Oxidation State Intermediates. J Org Chem 2022; 87:12096-12108. [PMID: 36066858 DOI: 10.1021/acs.joc.2c01202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Triple OsO4-mediated dihydroxylation of meso-tetrakis(pentafluorophenyl)porphyrin formed a non-aromatic hexahydroxypyrrocorphin as a single stereo-isomer. A one-step oxidative conversion of all three diol functionalities to lactone moieties generated three out of the four possible porphotrilactone regioisomers that were spectroscopically and structurally characterized. This conversion recovered most of the porphyrinic macrocycle aromatic ring current, as seen in their 1H NMR spectra and modeled using DFT computations. Stepwise OsO4-mediated dihydroxylations of porpho-mono- and -di-lactones generated intermediate oxidation state compounds between the pyrrole-three pyrroline macrocycle of the pyrrocorphin and the pyrrole-three oxazolone chromophore of the trilactones. The aromaticity of these chromophores was reduced with increasing number of oxazolone to pyrroline replacements, showing the importance for the presence of three lactone moieties for the retention of the macrocycle aromaticity in the tris-β,β'-modified macrocycles. This work first describes hexahydoxypyrrocorphins, porphotrislactones, and the oxidation state intermediates between them; furthers the understanding of the roles of β-lactone moieties in the expression of porphyrinic macrocycle aromaticity; and generally broadens access to chemically stable pyrrocorphins and pyrrocorphin analogues.
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Affiliation(s)
- Nisansala Hewage
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Matthew J Guberman-Pfeffer
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Nivedita Chaudhri
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Matthias Zeller
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084, United States
| | - José A Gascón
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
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8
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Chaudhri N, Guberman-Pfeffer MJ, Zeller M, Brückner C. Stepwise Reduction of β-Trioxopyrrocorphins: Collapse of the Oxo-Induced Macrocycle Aromaticity. J Org Chem 2022; 87:7179-7192. [PMID: 35605247 DOI: 10.1021/acs.joc.2c00399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The diatropic ring current that characterizes the unexpectedly aromatic octaethyltrioxopyrrocorphins gets drastically reduced upon chemical reduction of one and particularly two ketone moieties. With increasing reduction, the chromophores containing one pyrrole, one/two pyrrolinone, and one/two pyrrolines become more similar to regular, nonmacrocycle-aromatic pyrrocorphins (hexahydroporphyrins). Single-crystal diffraction analysis shows the reduction products to be idealized planar. With increasing reduction, their UV-vis spectroscopic signatures are those of conjugated but nonaromatic oligopyrroles. Their diatropic ring currents, as assessed by 1H NMR spectroscopy, showed them to possess largely nonaromatic π-systems. Dihydroxylation of select β,β'-dioxobacteriochlorin and β,β'-dioxoisobacteriochlorins also resulted in the formation of equivalent mixed pyrrole/two pyrrolinone/pyrroline chromophores. Computations were able to reproduce the experimental trends of the diatropic ring currents and filled in the data for the regioisomers that could not be experimentally accessed. The work further highlights the electronic influence of the β-oxo-substituents and, more specifically, the origin of the aromaticity of the trioxopyrrocorphins. It also presents a series of chemically robust pyrrocorphins, a chromophore class for which many chemically very sensitive members have been reported.
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Affiliation(s)
- Nivedita Chaudhri
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | | | - Matthias Zeller
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
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9
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Chaudhri N, Brückner C, Zeller M. Crystal structure of cis-7,8-dihy-droxy-5,10,15,20-tetra-phenyl-chlorin and its zinc(II)-ethyl-enedi-amine complex. Acta Crystallogr E Crystallogr Commun 2022; 78:392-398. [PMID: 35492263 PMCID: PMC8983991 DOI: 10.1107/s2056989022002729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 03/10/2022] [Indexed: 11/30/2022]
Abstract
The title chlorin, 2PhH2 , hydrogen-bonded to di-methyl-amino-pyridine (DMAP), C44H32N4O2·C7H10N2, and its corresponding zinc(II) complex, 2PhZn, axially coordinated to ethyl-enedi-amine (EDA), [Zn(C44H30N4O2)]·C2H8N2, were isolated and crystallized by adventitious reduction of the corresponding osmate esters by DMAP and EDA, respectively. Known since 1996 and, inter alia, used for the preparation of a wide range of (planar and non-planar) chlorin analogues (so-called pyrrole-modified porphyrins), their conformational analyses in the solid state are important benchmarks. Both macrocycles are only modestly distorted from planarity and both are slightly more non-planar than the corresponding dimeth-oxy-derivative, but less planar than a free-base meso-penta-fluoro-phenyl-based osmate ester. NSD analyses provide qu-anti-tative and qualitative analyses of the distortion modes. One origin of the non-planarity is presumably the avoidance of the eclipsed configuration of the two vic-cis diols on the pyrroline moiety; the resulting deformation of the pyrroline translates in some cases into the macrocycle. The structure of 2PhH2 features voids making up ca 26% of the unit-cell volume filled with highly disordered solvate mol-ecules (chloro-form and hexa-nes). 2PhZn crystallized with a 13.6 (4)% occupied solvate methanol mol-ecule.
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Affiliation(s)
- Nivedita Chaudhri
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA
| | - Matthias Zeller
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA
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10
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Thuita DW, Brückner C. Metal Complexes of Porphyrinoids Containing Nonpyrrolic Heterocycles. Chem Rev 2022; 122:7990-8052. [PMID: 35302354 DOI: 10.1021/acs.chemrev.1c00694] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The replacement of one or more pyrrolic building block(s) of a porphyrin by a nonpyrrolic heterocycle leads to the formation of so-called pyrrole-modified porphyrins (PMPs), porphyrinoids of broad structural variability. The wide range of coordination environments (type, number, charge, and architecture of the donor atoms) that the pyrrole-modified frameworks provide to the central metal ions, the frequent presence of donor atoms at their periphery, and their often observed nonplanarity or conformational flexibility distinguish the complexes of the PMPs clearly from those of the traditional square-planar, dianionic, N4-coordinating (hydro)porphyrins. Their different coordination properties suggest their utilization in areas beyond which regular metalloporphyrins are suitable. Following a general introduction to the synthetic methodologies available to generate pyrrole-modified porphyrins, their general structure, history, coordination chemistry, and optical properties, this Review highlights the chemical, electronic (optical), and structural differences of specific classes of metalloporphyrinoids containing nonpyrrolic heterocycles. The focus is on macrocycles with similar "tetrapyrrolic" architectures as porphyrins, thusly excluding the majority of expanded porphyrins. We highlight the relevance and application of these metal complexes in biological and technical fields as chemosensors, catalysts, photochemotherapeutics, or imaging agents. This Review provides an introduction to the field of metallo-PMPs as well as a comprehensive snapshot of the current state of the art of their synthesis, structures, and properties. It also aims to provide encouragement for the further study of these intriguing and structurally versatile metalloporphyrinoids.
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Affiliation(s)
- Damaris Waiyigo Thuita
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States
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11
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Brückner C, Chaudhri N, Nevonen DE, Bhattacharya S, Graf A, Kaesmann E, Li R, Guberman-Pfeffer MJ, Mani T, Nimthong-Roldán A, Zeller M, Chauvet AAP, Nemykin V. Structural and Photophysical Characterization of All Five Constitutional Isomers of the Octaethyl-β,β'-dioxo-bacterio- and -isobacteriochlorin Series. Chemistry 2021; 27:16189-16203. [PMID: 34535932 DOI: 10.1002/chem.202103014] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Indexed: 11/11/2022]
Abstract
It is well-known that treatment of β-octaethylporphyrin with H2 O2 /conc. H2 SO4 converts it to a β-oxochlorin as well as all five constitutional isomers of the corresponding β,β'-dioxo-derivatives: two bacteriochlorin-type isomers (β-oxo groups at opposite pyrrolic building blocks) and three isobacteriochlorin-type isomers (β-oxo-groups at adjacent pyrrolic building blocks). By virtue of the presence of the strongly electronically coupled β-oxo auxochromes, none of the chromophores are archetypical chlorins, bacteriochlorins, or isobacteriochlorins. Here the authors present, inter alia, the single crystal X-ray structures of all free-base diketone isomers and a comparative description of their UV-vis absorption spectra in neutral and acidic solutions, and fluorescence emission and singlet oxygen photosensitization properties, Magnetic Circular Dichroism (MCD) spectra, and singlet excited state lifetimes. DFT computations uncover underlying tautomeric equilibria and electronic interactions controlling their electronic properties, adding to the understanding of porphyrinoids carrying β-oxo functionalities. This comparative study lays the basis for their further study and utilization.
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Affiliation(s)
- Christian Brückner
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, United States
| | - Nivedita Chaudhri
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, United States
| | - Dustin E Nevonen
- Department of Chemistry, University of Manitoba Winnipeg, Manitoba, R3T 2 N2, Canada
| | - Sayantan Bhattacharya
- Department of Chemistry, University of Sheffield Dainton Building, Sheffield, S3 7HF, United Kingdom
| | - Arthur Graf
- Department of Chemistry, University of Sheffield Dainton Building, Sheffield, S3 7HF, United Kingdom
| | - Elizabeth Kaesmann
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, United States
| | - Ruoshi Li
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, United States
| | | | - Tomoyasu Mani
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, United States
| | - Arunpatcha Nimthong-Roldán
- Department of Chemistry, Youngstown State University One University Plaza, Youngstown, OH 44555-3663, United States
| | - Matthias Zeller
- Department of Chemistry, Youngstown State University One University Plaza, Youngstown, OH 44555-3663, United States.,Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907-2084, United States
| | - Adrien A P Chauvet
- Department of Chemistry, University of Sheffield Dainton Building, Sheffield, S3 7HF, United Kingdom
| | - Victor Nemykin
- Department of Chemistry, University of Manitoba Winnipeg, Manitoba, R3T 2 N2, Canada.,Department of Chemistry, University of Tennessee, 552 Buehler Hall, 1420 Circle Dr., Knoxville, TN, 37996-1600, United States
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12
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Nganga J, Chaudhri N, Brückner C, Angeles-Boza AM. β-Oxochlorin cobalt(II) complexes catalyze the electrochemical reduction of CO 2. Chem Commun (Camb) 2021; 57:4396-4399. [PMID: 33949479 DOI: 10.1039/d1cc00573a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Inspired by the architecture of the macrocycle of heme d1, a series of synthetic mono-, di- and tri-β-oxo-substituted porphyrinoid cobalt(ii) complexes were evaluated as electrocatalytic CO2 reducers, identifying complexes of unusually high efficiencies in generating multi-electron reduction products, including CH4.
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Affiliation(s)
- John Nganga
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, CT 06269, USA.
| | - Nivedita Chaudhri
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, CT 06269, USA.
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, CT 06269, USA.
| | - Alfredo M Angeles-Boza
- Department of Chemistry, University of Connecticut, 55 N. Eagleville Road, Storrs, CT 06269, USA. and Institute of Materials Science, University of Connecticut, 97 N. Eagleville Road, Storrs, CT 06269, USA.
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13
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Luciano MP, Atoyebi AO, Tardie W, Zeller M, Brückner C. Pyrrole-Modified Porphyrins Containing Eight-Membered Heterocycles Using a Reversal of the "Breaking and Mending" Strategy. J Org Chem 2020; 85:15273-15286. [PMID: 33174754 DOI: 10.1021/acs.joc.0c02108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The conversion of meso-aryl-porphyrins/chlorins to porphyrinoids containing nonpyrrolic heterocycles (so-called pyrrole-modified porphyrins, PMPs) along an approach we dubbed "the breaking and mending of porphyrins" is well known. However, examples are limited to the synthesis of PMPs containing up to six-membered heterocycles; the syntheses of larger rings failed. We report here hitherto unavailable eight-membered chlorin-type PMPs using an inverted "mending and breaking" approach. All examples are based on the addition of N,N'-dimethylurea derivatives to a meso-phenyl-β,β'-dioxoporphyrin, followed by oxidative cleavage of the intermediate diol adduct. We correlate the extremely nonplanar solid-state structures of three crystallographically characterized PMPs containing an eight-membered ring with their solution-state optical properties. The first examples of bis-modified, bacteriochlorin-type PMPs containing either two eight-membered rings or an eight-membered ring and an imidazolone ring are also detailed. Using other N,N'-nucleophiles failed to either generate chlorins containing a β,β'-dihydroxypyrroline, a prerequisite for the "breaking step," or the cleavage of those substrates that did generate a diol underwent subsequent reactions that thwarted the generation of the desired PMPs. This contribution adds novel PMPs containing eight-membered rings, highlights the effects these derivatizations have on the macrocycle conformation, and how that affects their optical properties.
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Affiliation(s)
- Michael P Luciano
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Adewole O Atoyebi
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Weston Tardie
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Matthias Zeller
- Department of Chemistry, Purdue University, 101 Wetherill Hall, 560 Oval Drive, West Lafayette, Indiana 47907-2084, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
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14
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Thuita D, Damunupola D, Brückner C. Oxazolochlorins 21. Most Efficient Access to meso-Tetraphenyl- and meso-Tetrakis(pentafluorophenyl)porpholactones, and Their Zinc(II) and Platinum(II) Complexes. Molecules 2020; 25:E4351. [PMID: 32972021 PMCID: PMC7570530 DOI: 10.3390/molecules25184351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 09/12/2020] [Accepted: 09/16/2020] [Indexed: 01/28/2023] Open
Abstract
meso-Phenyl- and meso-pentafluorophenyl-porpholactones, their metal complexes, as well as porphyrinoids directly derived from them are useful in a number of technical and biomedical applications, and more uses are expected to be discovered. About a dozen competing and complementary pathways toward their synthesis were reported. The suitability of the methods changes with the meso-aryl group and whether the free base or metal derivatives are sought. These circumstances make it hard for anyone outside of the field of synthetic porphyrin chemistry to ascertain which pathway is the best to produce which specific derivative. We report here on what we experimentally evaluated to be the most efficient pathways to generate the six key compounds from the commercially available porphyrins, meso-tetraphenylporphyrin (TPP) and meso-tetrakis(pentafluorophenyl)porphyrin (TFPP): free base meso-tetraphenylporpholactone (TPL) and meso-tetrakis(pentafluorophenyl)porpholactone (TFPL), and their platinum(II) and zinc(II) complexes TPLPt, TFPLPt, TPLZn, and TFPLZn, respectively. Detailed procedures are provided to make these intriguing molecules more readily available for their further study.
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Affiliation(s)
| | | | - Christian Brückner
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, CT 06269–3060, USA; (D.T.); (D.D.)
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15
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Jin GQ, Xue HZ, Zhang JL. Porpholactone Chemistry: Shining New Light on an Old Cofactor. Chempluschem 2020; 86:71-81. [PMID: 32844583 DOI: 10.1002/cplu.202000494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/30/2020] [Indexed: 02/06/2023]
Abstract
The emergence of porpholactone chemistry, discovered over 30 years ago, has significantly stimulated the development of biomimetic tetrapyrrole chemistry. It offers an opportunity, through modifications of non-pyrrolic building blocks, to clarify the relationship between chemical structure and excited-state properties, deciphering the structural code for the biological functions of life pigments. With intriguing photophysical properties in the red to near-infrared (NIR) regions, facile modulation of their electronic nature by fine-tuning chemical structures, and coordination ability with diverse metal ions, these novel porphyrinoids have favorable prospects in the fields of optical materials, bioimaging and therapy, and catalysis. In this Minireview, we summarize the brief history of porpholactone chemistry, and focus on the studies carried out in our group, particularly on the regioisomeric effect, NIR lanthanide luminescence, and metal catalysis. We outline the perspectives of these compounds in the construction of porpholactone-related biomedical applications and optical and energy materials, in order to inspire more interest and further advance bioinspired inorganic chemistry and lanthanide chemical biology.
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Affiliation(s)
- Guo-Qing Jin
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P.R. China
| | - Hao-Zong Xue
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P.R. China
| | - Jun-Long Zhang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P.R. China
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16
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Site-Selective Modification of a Porpholactone-Selective Synthesis of 12,13- and 17,18-Dihydroporpholactones. MOLECULES (BASEL, SWITZERLAND) 2020; 25:molecules25112642. [PMID: 32517216 PMCID: PMC7321334 DOI: 10.3390/molecules25112642] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 02/07/2023]
Abstract
The reaction of meso-tetrakis(pentafluorophenyl)porpholactone with azomethine ylides and nitrones affords pyrrolidine-fused and isoxazolidine-fused dihydroporpholactones that display, respectively, isobacteriochlorin- and chlorin-type UV–Vis spectra. These reactions are site-selective, yielding, respectively, 17,18- or 12,13-dihydroporpholactones. The crystal and molecular features of pyrrolidine-fused and isoxazolidine-fused dihydroporpholactones were unveiled from single-crystal X-ray diffraction studies.
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17
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Ning Y, Liu YW, Yang ZS, Yao Y, Kang L, Sessler JL, Zhang JL. Split and Use: Structural Isomers for Diagnosis and Therapy. J Am Chem Soc 2020; 142:6761-6768. [DOI: 10.1021/jacs.0c01155] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Yingying Ning
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
| | - Yi-Wei Liu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
| | - Zi-Shu Yang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
| | - Yuhang Yao
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
| | - Lei Kang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing 100034, P. R. China
| | - Jonathan L. Sessler
- Department of Chemistry, The University of Texas at Austin, 105 East 24th Street-A5300, Austin, Texas 78712-1224, United States
| | - Jun-Long Zhang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
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18
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Schnable D, Chaudhri N, Li R, Zeller M, Brückner C. Evaluation of Octaethyl-7,17-dioxobacteriochlorin as a Ligand for Transition Metals. Inorg Chem 2020; 59:2870-2880. [DOI: 10.1021/acs.inorgchem.9b03231] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- David Schnable
- Department of Chemistry, Unit 3060, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Nivedita Chaudhri
- Department of Chemistry, Unit 3060, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Ruoshi Li
- Department of Chemistry, Unit 3060, University of Connecticut, Storrs, Connecticut 06269-3060, United States
| | - Matthias Zeller
- Department of Chemistry, Purdue University, 101 Wetherill Hall, 560 Oval Drive, West Lafayette, Indiana 47907-2084, United States
| | - Christian Brückner
- Department of Chemistry, Unit 3060, University of Connecticut, Storrs, Connecticut 06269-3060, United States
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19
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Brückner C, Atoyebi AO, Girouard D, Lau KSF, Akhigbe J, Samankumara L, Damunupola D, Khalil GE, Gouterman M, Krause JA, Zeller M. Stepwise Preparation of
meso
‐Tetraphenyl‐ and
meso
‐Tetrakis(4‐trifluoromethylphenyl)bacteriodilactones and their Zinc(II) and Palladium(II) Complexes. European J Org Chem 2020. [DOI: 10.1002/ejoc.201901727] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Christian Brückner
- Department of Chemistry University of Connecticut 06268‐3060 Storrs CT USA
| | - Adewole O. Atoyebi
- Department of Chemistry University of Connecticut 06268‐3060 Storrs CT USA
| | - Derek Girouard
- Department of Chemistry University of Connecticut 06268‐3060 Storrs CT USA
| | - Kimberly S. F. Lau
- Department of Chemistry University of Connecticut 06268‐3060 Storrs CT USA
- Department of Chemistry University of Washington 98195 Seattle WA USA
| | - Joshua Akhigbe
- Department of Chemistry University of Connecticut 06268‐3060 Storrs CT USA
| | - Lalith Samankumara
- Department of Chemistry University of Connecticut 06268‐3060 Storrs CT USA
| | - Dinusha Damunupola
- Department of Chemistry University of Connecticut 06268‐3060 Storrs CT USA
| | - Gamal E. Khalil
- Department of Chemistry University of Washington 98195 Seattle WA USA
| | - Martin Gouterman
- Department of Chemistry University of Washington 98195 Seattle WA USA
| | - Jeanette A. Krause
- Department of Chemistry University of Cincinnati 45221‐0172 Cincinnati OH USA
| | - Matthias Zeller
- Department of Chemistry Purdue University 47907‐2084 West Lafayette IN USA
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20
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Burns AS, Dooley C, Carlson PR, Ziller JW, Rychnovsky SD. Relative and Absolute Structure Assignments of Alkenes Using Crystalline Osmate Derivatives for X-ray Analysis. Org Lett 2019; 21:10125-10129. [DOI: 10.1021/acs.orglett.9b04133] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Alexander S. Burns
- Department of Chemistry, University of California at Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Charles Dooley
- Department of Chemistry, University of California at Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Paul R. Carlson
- Department of Chemistry, University of California at Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Joseph W. Ziller
- Department of Chemistry, University of California at Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Scott D. Rychnovsky
- Department of Chemistry, University of California at Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
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21
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Ning Y, Jin GQ, Zhang JL. Porpholactone Chemistry: An Emerging Approach to Bioinspired Photosensitizers with Tunable Near-Infrared Photophysical Properties. Acc Chem Res 2019; 52:2620-2633. [PMID: 31298833 DOI: 10.1021/acs.accounts.9b00119] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Chlorophylls, known as the key building blocks of natural light-harvesting antennae, are essential to utilize solar energy from visible to near-infrared (NIR) region during the photosynthesis process. The fundamental studies for the relationship between structure and photophysical properties of chlorophylls disclosed the importance of β-peripheral modification and thus boosted the fast growth of NIR absorbing/emissive porphyrinoids via altering the extent of π-conjugation and the degree of distortion from the planarity of macrocycle. Despite the tremendous progress made in various porphyrin-based synthetic models, it still remains a challenge to precisely modulate photophysical properties through fine-tuning of β-peripheral structures in the way natural chlorophylls do. With this in mind, we initiated a program and focused on meso-C6F5-substituted porpholactone (F20TPPL), in which one β-pyrrolic double bond was replaced by a lactone moiety, as an attractive platform to construct the bioinspired library of NIR porphyrinoids. In this Account, we summarize our recent contributions to the bioinspired design, synthesis, photophysical characterization, and applications of porpholactones and their derivatives. We have developed a general, convenient method to directly prepare porpholactones in large scale up to gram, which forms the chemical basis of porpholactone chemistry. By modulation of the saturation level and in particular regioisomerization of β-dilactone moieties, a synthetic library constituted by a series of porpholactones and their derivatives has been established. Thanks to the electron-withdrawing nature of lactone moiety, derivation of the saturation levels gives help to build stable models for chlorin, bacteriochlorin, and tunichlorin. It is worth noting that regioisomerization of dilactone moieties mimics the relative orientation of β-substituents in natural chlorophylls and hemes, which was considered as the key factor to tune NIR absorption and reactivity. Porpholactones can illustrate the capability of fine-tuning photophysical properties including the excited triplet states by subtle alteration of β-peripheral structures in the presence of transition metals and lanthanides (Ln). Furthermore, they can serve as efficient photosensitizers for singlet oxygen and NIR Ln, showing potential applications in cell imaging and photocytotoxicity studies. The high luminescence, tunable structures, high cellular uptake, and intense NIR absorption render them as promising and competitive candidates for theranostics in vitro and in vivo. Therefore, extending the studies of "porpholactone chemistry" not only tests the fundamental understanding of the structure-function relationship that governs NIR photophysical properties of natural tetrapyrrole cofactors such as chlorophylls but also provides the guiding principles for the bioinspired design of NIR luminescent molecular probes with various applications. Taken together, as a new synthetic porphyrin derivative, porpholactone chemistry shines light on synthetic porphyrin, bioinorganic, and lanthanide chemistry.
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Affiliation(s)
- Yingying Ning
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
| | - Guo-Qing Jin
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
| | - Jun-Long Zhang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
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22
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Guberman-Pfeffer MJ, Lalisse RF, Hewage N, Brückner C, Gascón JA. Origins of the Electronic Modulations of Bacterio- and Isobacteriodilactone Regioisomers. J Phys Chem A 2019; 123:7470-7485. [PMID: 31361130 DOI: 10.1021/acs.jpca.9b05656] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Advances in the utilization of porphyrinoids for photomedicine, catalysis, and artificial photosynthesis require a fundamental understanding of the relationships between their molecular connectivity and resulting electronic structures. Herein, we analyze how the replacement of two pyrrolic Cβ═Cβ bonds of a porphyrin by two lactone (O═C-O) moieties modulates the ground-state thermodynamic stability and electronic structure of the resulting five possible pyrrole-modified porphyrin isomers. We made these determinations based on density functional theory (DFT) and time-dependent DFT computations of the optical spectra of all regioisomers. We also analyzed the computed magnetically induced currents of their aromatic π-systems. All regioisomers adopt the tautomeric state that maximizes aromaticity, whether or not transannular steric strains are incurred. In all isomers, the O═Cβ-Oβ bonds were found to support a macrocycle diatropic ring current. We attributed this to the delocalization of nonbonding electrons from the ring oxa- and oxo-atoms into the macrocycle. As a consequence of this delocalization, the dilactone regioisomers are as-or even more-aromatic than their hydroporphyrin congeners. The electronic structures follow different trends for the bacteriochlorin- and isobacteriochlorin-type isomers. The presence of either oxo- or oxa-oxygens conjugated with the macrocyclic π-system was found to be the minimal structural requirement for the regioisomers to exhibit distinct electronic properties. Our computational methods and mechanistic insights provide a basis for the systematic exploration of the physicochemical properties of porphyrinoids as a function of the number, relative orientation, and degree of macrocycle-π-conjugation of β-substituents, in general, and for dilactone-based porphyrinic chromophores, in particular.
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Affiliation(s)
- Matthew J Guberman-Pfeffer
- Department of Chemistry , University of Connecticut , Unit 3060 , Storrs , Connecticut 06269-3060 , United States
| | - Remy F Lalisse
- Department of Chemistry , University of Connecticut , Unit 3060 , Storrs , Connecticut 06269-3060 , United States
| | - Nisansala Hewage
- Department of Chemistry , University of Connecticut , Unit 3060 , Storrs , Connecticut 06269-3060 , United States
| | - Christian Brückner
- Department of Chemistry , University of Connecticut , Unit 3060 , Storrs , Connecticut 06269-3060 , United States
| | - José A Gascón
- Department of Chemistry , University of Connecticut , Unit 3060 , Storrs , Connecticut 06269-3060 , United States
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23
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Hohlfeld BF, Flanagan KJ, Kulak N, Senge MO, Christmann M, Wiehe A. Synthesis of Porphyrinoids, BODIPYs, and (Dipyrrinato)ruthenium(II) Complexes from Prefunctionalized Dipyrromethanes. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900530] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Benjamin F. Hohlfeld
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
- Institut für Chemie und Biochemie; Freie Universität Berlin; Fabeckstr. 34/36 14195 Berlin Germany
- biolitec research GmbH; Otto-Schott-Str. 15 07745 Jena Germany
| | - Keith J. Flanagan
- Medicinal Chemistry, Trinity Translational Medicine Institute; Trinity Centre for Health Sciences, Trinity College Dublin; The University of Dublin, St James's Hospital; 8 Dublin Ireland
| | - Nora Kulak
- Institut für Chemie und Biochemie; Freie Universität Berlin; Fabeckstr. 34/36 14195 Berlin Germany
| | - Mathias O. Senge
- Medicinal Chemistry, Trinity Translational Medicine Institute; Trinity Centre for Health Sciences, Trinity College Dublin; The University of Dublin, St James's Hospital; 8 Dublin Ireland
| | - Mathias Christmann
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
| | - Arno Wiehe
- Institut für Chemie und Biochemie; Freie Universität Berlin; Takustr. 3 14195 Berlin Germany
- biolitec research GmbH; Otto-Schott-Str. 15 07745 Jena Germany
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Atoyebi AO, Brückner C. Observations on the Mechanochemical Insertion of Zinc(II), Copper(II), Magnesium(II), and Select Other Metal(II) Ions into Porphyrins. Inorg Chem 2019; 58:9631-9642. [DOI: 10.1021/acs.inorgchem.9b00052] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Adewole O. Atoyebi
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
| | - Christian Brückner
- Department of Chemistry, University of Connecticut, Unit 3060, Storrs, Connecticut 06269-3060, United States
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