1
|
Kole GK, Košćak M, Amar A, Majhen D, Božinović K, Brkljaca Z, Ferger M, Michail E, Lorenzen S, Friedrich A, Krummenacher I, Moos M, Braunschweig H, Boucekkine A, Lambert C, Halet JF, Piantanida I, Müller-Buschbaum K, Marder TB. Methyl Viologens of Bis-(4'-Pyridylethynyl)Arenes - Structures, Photophysical and Electrochemical Studies, and their Potential Application in Biology. Chemistry 2022; 28:e202200753. [PMID: 35502627 PMCID: PMC9400870 DOI: 10.1002/chem.202200753] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Indexed: 12/20/2022]
Abstract
A series of bis‐(4’‐pyridylethynyl)arenes (arene=benzene, tetrafluorobenzene, and anthracene) were synthesized and their bis‐N‐methylpyridinium compounds were investigated as a class of π‐extended methyl viologens. Their structures were determined by single crystal X‐ray diffraction, and their photophysical and electrochemical properties (cyclic voltammetry), as well as their interactions with DNA/RNA were investigated. The dications showed bathochromic shifts in emission compared to the neutral compounds. The neutral compounds showed very small Stokes shifts, which are a little larger for the dications. All of the compounds showed very short fluorescence lifetimes (<4 ns). The neutral compound with an anthracene core has a quantum yield of almost unity. With stronger acceptors, the analogous bis‐N‐methylpyridinium compound showed a larger two‐photon absorption cross‐section than its neutral precursor. All of the dicationic compounds interact with DNA/RNA; while the compounds with benzene and tetrafluorobenzene cores bind in the grooves, the one with an anthracene core intercalates as a consequence of its large, condensed aromatic linker moiety, and it aggregates within the polynucleotide when in excess over DNA/RNA. Moreover, all cationic compounds showed highly specific CD spectra upon binding to ds‐DNA/RNA, attributed to the rare case of forcing the planar, achiral molecule into a chiral rotamer, and negligible toxicity toward human cell lines at ≤10 μM concentrations. The anthracene‐analogue exhibited intracellular accumulation within lysosomes, preventing its interaction with cellular DNA/RNA. However, cytotoxicity was evident at 1 μM concentration upon exposure to light, due to singlet oxygen generation within cells. These multi‐faceted features, in combination with its two‐photon absorption properties, suggest it to be a promising lead compound for development of novel light‐activated theranostic agents.
Collapse
Affiliation(s)
- Goutam Kumar Kole
- Institut für Anorganische Chemie, and, Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Department of Chemistry, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur, Tamil Nadu, 603203, India
| | - Marta Košćak
- Ruđer Bošković Institute, 10000, Zagreb, Croatia
| | - Anissa Amar
- Laboratoire de Physique et Chimie Quantiques, Université Mouloud Mammeri, Tizi Ouzou, 15000 Tizi-Ouzou, Algeria
| | | | | | | | - Matthias Ferger
- Institut für Anorganische Chemie, and, Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Evripidis Michail
- Institut für Organische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Sabine Lorenzen
- Institut für Anorganische Chemie, and, Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Alexandra Friedrich
- Institut für Anorganische Chemie, and, Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Ivo Krummenacher
- Institut für Anorganische Chemie, and, Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Michael Moos
- Institut für Organische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Holger Braunschweig
- Institut für Anorganische Chemie, and, Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Abdou Boucekkine
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, Institut des Sciences Chimiques de Rennes UMR 6226, 35000, Rennes, France
| | - Christoph Lambert
- Institut für Organische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Jean-François Halet
- Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, Institut des Sciences Chimiques de Rennes UMR 6226, 35000, Rennes, France.,CNRS-Saint-Gobain-NIMS, IRL 3629, Laboratory for Innovative Key Materials and Structures (LINK), National Institute for Materials Science (NIMS), Tsukuba, 305-0044, Japan
| | | | - Klaus Müller-Buschbaum
- Institut für Anorganische und Analytische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392, Gießen, Germany
| | - Todd B Marder
- Institut für Anorganische Chemie, and, Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| |
Collapse
|
2
|
Frogley BJ, Hill AF, Welsh SS. Symmetric and non-symmetric anthracen-diyl bis(alkylidynes). Dalton Trans 2021; 50:15502-15523. [PMID: 34676857 DOI: 10.1039/d1dt02537f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three examples of 9-bromo-10-(alkylidynyl)anthracenes, [W{CC(C6H4)2CBr}(CO)2(L)] (L = hydrotris(dimethylpyrazol-1-yl)borate Tp*, hydrotris(pyrazol-1-yl)borate Tp, hydrotris(2-mercapto-N-methylimidazol-1-yl)borate Tm) were prepared via modified Fischer-Mayr acyl oxide-abstraction protocols. With a sufficiently bulky ancillary ligand (L = Tp*) the aryl bromide is ammenable to cross-coupling reactions that enable more elaborate derivatives to be prepared. These including symmetric bis(alkylidynyl)anthracenes as well as non-palindromic examples bearing disparate metals and/or co-ligands. In contrast, these couplings fail for smaller ligands (L = Tp, Tm) where it was found that Pd0 or Pt0 were instead able to coordinate across two WC bonds to give trimetallic bow-tie complexes, [W2M{μ-CC(C6H4)2CBr}2(CO)4(L)2] (M = Pd, Pt; L = Tp, Tm).
Collapse
Affiliation(s)
- Benjamin J Frogley
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory, ACT 2601, Australia.
| | - Anthony F Hill
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory, ACT 2601, Australia.
| | - Steven S Welsh
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory, ACT 2601, Australia.
| |
Collapse
|
3
|
Li K, Chen Y, Wang J, Yang C. Diverse emission properties of transition metal complexes beyond exclusive single phosphorescence and their wide applications. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213755] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
4
|
Naher M, Bock S, Langtry ZM, O’Malley KM, Sobolev AN, Skelton BW, Korb M, Low PJ. Synthesis, Structure and Physical Properties of “Wire-like” Metal Complexes. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00685] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Masnun Naher
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Sören Bock
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Zakary M. Langtry
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Kieran M. O’Malley
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Alexandre N. Sobolev
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Brian W. Skelton
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Marcus Korb
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Paul J. Low
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| |
Collapse
|
5
|
Maier J, Deutsch M, Merz J, Ye Q, Diamond O, Schilling M, Friedrich A, Engels B, Marder TB. Highly Conjugated π-Systems Arising from Cannibalistic Hexadehydro-Diels-Alder Couplings: Cleavage of C-C Single and Triple Bonds. Chemistry 2020; 26:15989-16000. [PMID: 32619049 PMCID: PMC7756338 DOI: 10.1002/chem.202002511] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Indexed: 11/30/2022]
Abstract
We have investigated the cannibalistic self-trapping reaction of an ortho-benzyne derivative generated from 1,11-bis(p-tolyl)undeca-1,3,8,10-tetrayne in an HDDA reaction. Without adding any specific trapping agent, the highly reactive benzyne is trapped by another bisdiyne molecule in at least three different modes. We have isolated and characterized the resulting products and performed high-level calculations concerning the reaction mechanism. During the cannibalistic self-trapping process, either a C≡C triple bond or an sp-sp3 C-C single bond is cleaved. Up to seven rings and nine C-C bonds are formed starting from two 1,11-bis(p-tolyl)undeca-1,3,8,10-tetrayne molecules. Our experiments and calculations provide considerable insight into the variety of reaction pathways which the ortho-benzyne derivative, generated from a bisdiyne, can take when reacting with another bisdiyne molecule.
Collapse
Affiliation(s)
- Jan Maier
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry &, Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Marian Deutsch
- Institut für Physikalische und Theoretische Chemie, Julius-Maximilians-Universität WürzburgEmil-Fischer-Straße 4297074WürzburgGermany
| | - Julia Merz
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry &, Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Qing Ye
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry &, Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Southern University of Science and TechnologyNo 1088, Xueyuan Rd.Xili, Nanshan DistrictShenzhen, GuangdongP. R. China
| | - Oliver Diamond
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry &, Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Maja‐Tessa Schilling
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry &, Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Alexandra Friedrich
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry &, Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Bernd Engels
- Institut für Physikalische und Theoretische Chemie, Julius-Maximilians-Universität WürzburgEmil-Fischer-Straße 4297074WürzburgGermany
| | - Todd B. Marder
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry &, Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| |
Collapse
|
6
|
Heß M, Stennett TE, Fantuzzi F, Bertermann R, Schock M, Schäfer M, Thiess T, Braunschweig H. Diverse ring-opening reactions of rhodium η 4-azaborete complexes. Chem Sci 2020; 11:9134-9140. [PMID: 34123162 PMCID: PMC8163374 DOI: 10.1039/d0sc02283g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Sequential treatment of [Rh(COE)2Cl]2 (COE = cyclooctene) with PiPr3, alkyne derivatives and tBuN
Created by potrace 1.16, written by Peter Selinger 2001-2019
]]>
BMes (Mes = 2,4,6-trimethylphenyl) provided functionalized rhodium η4-1,2-azaborete complexes of the form (η4-azaborete)RhCl(PiPr3). The scope of this reaction was expanded to encompass alkynes with hydrogen, alkyl, aryl, ferrocenyl, alkynyl, azaborinyl and boronate ester substituents. Treatment of these complexes with PMe3 led to insertion of the rhodium atom into the B–C bond of the BNC2 ring, forming 1-rhoda-3,2-azaboroles. Addition of N-heterocyclic carbenes to azaborete complexes led to highly unusual rearrangements to rhodium η2,κ1-allenylborylamino complexes via deprotonation and C–N bond cleavage. Heating and photolysis of an azaborete complex also led to rupture of the C–N bond followed by subsequent rearrangements, yielding an η4-aminoborylallene complex and two isomeric η4-butadiene complexes. Rhodium η4-azaborete complexes can be transformed into a variety of species with ring-opened, BN-containing ligands by treatment with Lewis bases.![]()
Collapse
Affiliation(s)
- Merlin Heß
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Tom E. Stennett
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Rüdiger Bertermann
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Marvin Schock
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Marius Schäfer
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Torsten Thiess
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| |
Collapse
|
7
|
Weber SM, Hilt G. Chemoselective Cobalt(I)-Catalyzed Cyclotrimerization of (Un)Symmetrical 1,3-Butadiynes for the Synthesis of 1,2,4-Regioisomers. Org Lett 2019; 21:4106-4110. [DOI: 10.1021/acs.orglett.9b01281] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Sebastian M. Weber
- Fachbereich Chemie Philipps Universität Marburg, Hans-Meerwein Strasse 4, D-35032 Marburg, Germany
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, D-26111 Oldenburg, Germany
| | - Gerhard Hilt
- Fachbereich Chemie Philipps Universität Marburg, Hans-Meerwein Strasse 4, D-35032 Marburg, Germany
- Institut für Chemie, Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, D-26111 Oldenburg, Germany
| |
Collapse
|
8
|
Cardozo C, Mendoza A, Farías G, Formiga ALB, Peña D, Fuentes F, Arce A, Otero Y. Synthesis of rhenacyclopentadienes and η2:η2-diyne complexes from a labile dirhenium carbonyl and π-conjugated 1,7-octadiynes: Structural and photophysical characterization. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2018.12.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
9
|
Yao Y, Yin HY, Ning Y, Wang J, Meng YS, Huang X, Zhang W, Kang L, Zhang JL. Strong Fluorescent Lanthanide Salen Complexes: Photophysical Properties, Excited-State Dynamics, and Bioimaging. Inorg Chem 2018; 58:1806-1814. [PMID: 30576111 DOI: 10.1021/acs.inorgchem.8b02376] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis, excited-state dynamics, and biological application of luminescent lanthanide salen complexes (Ln = Lu, Gd, Eu, Yb, salen = N, N'-bis(salicylidene)ethylenediamine-based ligands) with sandwich structures are described. Among them, Lu(III) complexes show unusually strong ligand-centered fluorescence with quantum yields up to 62%, although the metal center is close to a chromophore ligand. The excited-state dynamic studies including ultrafast spectroscopy for Ln-salen complexes revealed that their excited states are solely dependent on the salen ligands and the ISC rates are slow (108-109 s-1). Importantly, time-dependent density functional theory calculations attribute the low energy transfer efficiency to the weak spin-orbital coupling (SOC) between the singlet and triplet excited states. More importantly, Lu-salen has been applied as a molecular platform to construct fluorescence probes with organelle specificity in living cell imaging, which demonstrates the advantages of the sandwich structures as being capable of preventing intramolecular metal-ligand interactions and behaviors different from those of the previously reported Zn-salens. Most importantly, the preliminary study for in vivo imaging using a mouse model demonstrated the potential application of Ln coordination complexes in therapeutic and diagnostic bioimaging beyond living cells or in vitro.
Collapse
Affiliation(s)
- Yuhang Yao
- 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 , People's Republic of China
| | - Hao-Yan Yin
- 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 , People's Republic of China
| | - Yingying Ning
- 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 , People's Republic of China
| | - Jian Wang
- Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry , Jilin University , Changchun 130023 , People's Republic of China
| | - Yin-Shan Meng
- 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 , People's Republic of China
| | - Xinyue Huang
- Center for Advanced Quantum Studies, Department of Physics and Applied Optics Beijing Area Major Laboratory , Beijing Normal University , Beijing 100875 , People's Republic of China
| | - Wenkai Zhang
- Center for Advanced Quantum Studies, Department of Physics and Applied Optics Beijing Area Major Laboratory , Beijing Normal University , Beijing 100875 , People's Republic of China
| | - Lei Kang
- Department of Nuclear Medicine , Peking University First Hospital , Beijing 100034 , People's Republic of 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 , People's Republic of China
| |
Collapse
|
10
|
Tian YM, Guo XN, Kuntze-Fechner MW, Krummenacher I, Braunschweig H, Radius U, Steffen A, Marder TB. Selective Photocatalytic C-F Borylation of Polyfluoroarenes by Rh/Ni Dual Catalysis Providing Valuable Fluorinated Arylboronate Esters. J Am Chem Soc 2018; 140:17612-17623. [PMID: 30474979 DOI: 10.1021/jacs.8b09790] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A highly selective and general photocatalytic C-F borylation protocol that employs a rhodium biphenyl complex as a triplet sensitizer and the nickel catalyst [Ni(IMes)2] (IMes = 1,3-dimesitylimidazoline-2-ylidene) for the C-F bond activation and defluoroborylation process is reported. This tandem catalyst system operates with visible (blue, 400 nm) light and achieves borylation of a wide range of fluoroarenes with B2pin2 at room temperature in excellent yields and with high selectivity. Direct irradiation of the intermediary C-F bond oxidative addition product trans-[NiF(ArF)(IMes)2] leads to very fast decomposition when B2pin2 is present. This destructive pathway can be bypassed by indirect excitation of the triplet states of the nickel(II) complex via the photoexcited rhodium biphenyl complex. Mechanistic studies suggest that the exceptionally long-lived triplet excited state of the Rh biphenyl complex used as the photosensitizer allows for efficient triplet energy transfer to trans-[NiF(ArF)(IMes)2], which leads to dissociation of one of the NHC ligands. This contrasts with the majority of current photocatalytic transformations, which employ transition metals as excited state single electron transfer agents. We have previously reported that C(arene)-F bond activation with [Ni(IMes)2] is facile at room temperature, but that the transmetalation step with B2pin2 is associated with a high energy barrier. Thus, this triplet energy transfer ultimately leads to a greatly enhanced rate constant for the transmetalation step and thus for the whole borylation process. While addition of a fluoride source such as CsF enhances the yield, it is not absolutely required. We attribute this yield-enhancing effect to (i) formation of an anionic adduct of B2pin2, i.e., FB2pin2-, as an efficient, much more nucleophilic {Bpin-} transfer reagent for the borylation/transmetalation process, and/or (ii) trapping of the Lewis acidic side product FBpin by formation of [F2Bpin]- to avoid the formation of a significant amount of NHC-FBpin and consequently decomposition of {Ni(NHC)2} species in the reaction mixture.
Collapse
Affiliation(s)
- Ya-Ming Tian
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| | - Xiao-Ning Guo
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| | - Maximilian W Kuntze-Fechner
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| | - Ivo Krummenacher
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| | - Holger Braunschweig
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| | - Udo Radius
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| | - Andreas Steffen
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| | - Todd B Marder
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry & Catalysis with Boron , Julius-Maximilians-Universität Würzburg , Am Hubland, 97074 Würzburg , Germany
| |
Collapse
|
11
|
Haque A, Al-Balushi RA, Al-Busaidi IJ, Khan MS, Raithby PR. Rise of Conjugated Poly-ynes and Poly(Metalla-ynes): From Design Through Synthesis to Structure-Property Relationships and Applications. Chem Rev 2018; 118:8474-8597. [PMID: 30112905 DOI: 10.1021/acs.chemrev.8b00022] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Conjugated poly-ynes and poly(metalla-ynes) constitute an important class of new materials with potential application in various domains of science. The key factors responsible for the diverse usage of these materials is their intriguing and tunable chemical and photophysical properties. This review highlights fascinating advances made in the field of conjugated organic poly-ynes and poly(metalla-ynes) incorporating group 4-11 metals. This includes several important aspects of conjugated poly-ynes viz. synthetic protocols, bonding, electronic structure, nature of luminescence, structure-property relationships, diverse applications, and concluding remarks. Furthermore, we delineated the future directions and challenges in this particular area of research.
Collapse
Affiliation(s)
- Ashanul Haque
- Department of Chemistry , Sultan Qaboos University , P.O. Box 36, Al-Khod 123 , Sultanate of Oman
| | - Rayya A Al-Balushi
- Department of Chemistry , Sultan Qaboos University , P.O. Box 36, Al-Khod 123 , Sultanate of Oman
| | - Idris Juma Al-Busaidi
- Department of Chemistry , Sultan Qaboos University , P.O. Box 36, Al-Khod 123 , Sultanate of Oman
| | - Muhammad S Khan
- Department of Chemistry , Sultan Qaboos University , P.O. Box 36, Al-Khod 123 , Sultanate of Oman
| | - Paul R Raithby
- Department of Chemistry , University of Bath , Claverton Down , Bath BA2 7AY , U.K
| |
Collapse
|
12
|
Completely Unexpected Coordination Selectivity of Copper Iodide for Thioether Over Ethynyl. CHEMISTRY AFRICA 2018. [DOI: 10.1007/s42250-018-0004-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
13
|
Barwick-Silk J, Hardy S, Willis MC, Weller AS. Rh(DPEPhos)-Catalyzed Alkyne Hydroacylation Using β-Carbonyl-Substituted Aldehydes: Mechanistic Insight Leads to Low Catalyst Loadings that Enables Selective Catalysis on Gram-Scale. J Am Chem Soc 2018; 140:7347-7357. [PMID: 29763563 DOI: 10.1021/jacs.8b04086] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The detailed mechanism of the hydroacylation of β-amido-aldehyde, 2,2-dimethyl-3-morpholino-3-oxopropanal, with 1-octyne using [Rh( cis-κ2-P,P-DPEPhos)(acetone)2][BArF4]-based catalysts, is described [ArF = (CF3)2C6H3]. A rich mechanistic landscape of competing and interconnected hydroacylation and cyclotrimerization processes is revealed. An acyl-hydride complex, arising from oxidative addition of aldehyde, is the persistent resting state during hydroacylation, and quaternary substitution at the β-amido-aldehyde strongly disfavors decarbonylation. Initial rate, KIE, and labeling studies suggest that the migratory insertion is turnover-limiting as well as selectivity determining for linear/branched products. When the concentration of free aldehyde approaches zero at the later stages of catalysis alkyne cyclotrimerization becomes competitive, to form trisubstituted hexylarenes. At this point, the remaining acyl-hydride turns over in hydroacylation and the free alkyne is now effectively in excess, and the resting state moves to a metallacyclopentadiene and eventually to a dormant α-pyran-bound catalyst complex. Cyclotrimerization thus only becomes competitive when there is no aldehyde present in solution, and as aldehyde binds so strongly to form acyl-hydride when this happens will directly correlate to catalyst loading: with low loadings allowing for free aldehyde to be present for longer, and thus higher selectivites to be obtained. Reducing the catalyst loading from 20 mol % to 0.5 mol % thus leads to a selectivity increase from 96% to ∼100%. An optimized hydroacylation reaction is described that delivers gram scale of product, at essentially quantitative levels, using no excess of either reagent, at very low catalyst loadings, using minimal solvent, with virtually no workup.
Collapse
Affiliation(s)
- James Barwick-Silk
- Department of Chemistry, Chemistry Research Laboratories , University of Oxford , Mansfield Road , Oxford OX1 4TA , U.K
| | - Simon Hardy
- Early Chemical Development , Pharmaceutical Sciences, IMED Biotech Unit, AstraZeneca , Macclesfield SK10 2NA , U.K
| | - Michael C Willis
- Department of Chemistry, Chemistry Research Laboratories , University of Oxford , Mansfield Road , Oxford OX1 4TA , U.K
| | - Andrew S Weller
- Department of Chemistry, Chemistry Research Laboratories , University of Oxford , Mansfield Road , Oxford OX1 4TA , U.K
| |
Collapse
|
14
|
Convenient synthetic access to fluorescent rhodacyclopentadienes via ligand exchange reactions. J Organomet Chem 2017. [DOI: 10.1016/j.jorganchem.2017.02.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
15
|
Chan KT, Tong GSM, To WP, Yang C, Du L, Phillips DL, Che CM. The interplay between fluorescence and phosphorescence with luminescent gold(i) and gold(iii) complexes bearing heterocyclic arylacetylide ligands. Chem Sci 2016; 8:2352-2364. [PMID: 28451340 PMCID: PMC5365001 DOI: 10.1039/c6sc03775e] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 12/03/2016] [Indexed: 01/02/2023] Open
Abstract
The photophysical properties of a series of gold(i) [LAu(C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 CR)] (L = PCy3 (1a-4a), RNC (5a), NHC (6a)) and gold(iii) complexes [Au(C^N^C)(CCR)] (1b-4b) bearing heterocyclic arylacetylide ligands with narrow band-gap are compared. The luminescence of both series are derived from an intraligand transition localized on the arylacetylide ligand (ππ*(CCR)) but 1a-3a displayed prompt fluorescence (τPF = 2.7-12.0 ns) while 1b-3b showed mainly phosphorescence (τPh = 104-205 μs). The experimentally determined intersystem crossing (ISC) rate constants (kISC) are on the order of 106 to 108 s-1 for the gold(i) series (1a-3a) but 1010 to 1011 s-1 for the gold(iii) analogues (1b-3b). DFT/TDDFT calculations have been performed to help understand the difference in the kISC between the two series of complexes. Owing to the different oxidation states of the gold ion, the Au(i) complexes have linear coordination geometry while the Au(iii) complexes are square planar. It was found from DFT/TDDFT calculations that due to this difference in coordination geometries, the energy gap between the singlet and triplet excited states (ΔEST) with effective spin-orbit coupling (SOC) for Au(i) systems is much larger than that for the Au(iii) counterparts, thus resulting in the poor ISC efficiency for the former. Time-resolved spectroscopies revealed a minor contribution (<2.9%) of a long-lived delayed fluorescence (DF) (τDF = 4.6-12.5 μs) to the total fluorescence in 1a-3a. Attempts have been made to elucidate the mechanism for the origins of the DF: the dependence of the DF intensity with the power of excitation light reveals that triplet-triplet annihilation (TTA) is the most probable mechanism for the DF of 1a while germinate electron-hole pair (GP) recombination accounts for the DF of 2a in 77 K glassy solution (MeOH/EtOH = 4 : 1). Both 4a and 4b contain a BODIPY moiety at the acetylide ligand and display only 1IL(ππ*) fluorescence with negligible phosphorescence being observed. Computational analyses attributed this observation to the lack of low-lying triplet excited states that could have effective SOC with the S1 excited state.
Collapse
Affiliation(s)
- Kaai Tung Chan
- State Key Laboratory of Synthetic Chemistry , Institute of Molecular Functional Materials , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China . ;
| | - Glenna So Ming Tong
- State Key Laboratory of Synthetic Chemistry , Institute of Molecular Functional Materials , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China . ;
| | - Wai-Pong To
- State Key Laboratory of Synthetic Chemistry , Institute of Molecular Functional Materials , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China . ;
| | - Chen Yang
- State Key Laboratory of Synthetic Chemistry , Institute of Molecular Functional Materials , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China . ;
| | - Lili Du
- Department of Chemistry , The University of Hong Kong , Hong Kong , China
| | - David Lee Phillips
- Department of Chemistry , The University of Hong Kong , Hong Kong , China
| | - Chi-Ming Che
- State Key Laboratory of Synthetic Chemistry , Institute of Molecular Functional Materials , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China . ; .,Department of Chemistry , HKU Shenzhen Institute of Research and Innovation , Shenzhen 518053 , China
| |
Collapse
|
16
|
Zhou J, Gai L, Zhou Z, Yang W, Mack J, Xu K, Zhao J, Zhao Y, Qiu H, Chan KS, Shen Z. Rational Design of Emissive NIR-Absorbing Chromophores: Rh(III) Porphyrin-Aza-BODIPY Conjugates with Orthogonal Metal-Carbon Bonds. Chemistry 2016; 22:13201-9. [PMID: 27516405 DOI: 10.1002/chem.201602670] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Indexed: 11/08/2022]
Abstract
The facile synthesis of Group 9 Rh(III) porphyrin-aza-BODIPY conjugates that are linked through an orthogonal Rh-C(aryl) bond is reported. The conjugates combine the advantages of the near-IR (NIR) absorption and intense fluorescence of aza-BODIPY dyes with the long-lived triplet states of transition metal rhodium porphyrins. Only one emission peak centered at about 720 nm is observed, irrespective of the excitation wavelength, demonstrating that the conjugates act as unique molecules rather than as dyads. The generation of a locally excited (LE) state with intramolecular charge-transfer (ICT) character has been demonstrated by solvatochromic effects in the photophysical properties, singlet oxygen quantum yields in polar solvents, and by the results of density functional theory (DFT) calculations. In nonpolar solvents, the Rh(III) conjugates exhibit strong aza-BODIPY-centered fluorescence at around 720 nm (ΦF =17-34 %), and negligible singlet oxygen generation. In polar solvents, enhancements of the singlet-oxygen quantum yield (ΦΔ =19-27 %, λex =690 nm) have been observed. Nanosecond pulsed time-resolved absorption spectroscopy confirms that relatively long-lived triplet excited states are formed. The synthetic methodology outlined herein provides a useful strategy for the assembly of functional materials that are highly desirable for a wide range of applications in material science and biomedical fields.
Collapse
Affiliation(s)
- Jinfeng Zhou
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Lizhi Gai
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, P. R. China
| | - Zhikuan Zhou
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Wu Yang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, P. R. China
| | - John Mack
- Department of Chemistry, Rhodes University, Grahamstown, 6140, South Africa.
| | - Kejing Xu
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116000, P. R. China
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116000, P. R. China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Hailin Qiu
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China
| | - Kin Shing Chan
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, P. R. China.
| | - Zhen Shen
- State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, P. R. China.
| |
Collapse
|
17
|
Shafikov MZ, Kozhevnikov DN, Bodensteiner M, Brandl F, Czerwieniec R. Modulation of Intersystem Crossing Rate by Minor Ligand Modifications in Cyclometalated Platinum(II) Complexes. Inorg Chem 2016; 55:7457-66. [PMID: 27388146 DOI: 10.1021/acs.inorgchem.6b00704] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Photophysical properties of four new platinum(II) complexes comprising extended ppy (Hppy = 2-phenylpyridine) and thpy (Hthpy = 2-(2'-thienyl)pyridine) cyclometalated ligands and acetylacetonate (acac) are reported. Substitution of the benzene ring of Pt-ppy complexes 1 and 2 with a more electron-rich thiophene of Pt-thpy complexes 3 and 4 leads to narrowing of the HOMO-LUMO gap and thus to a red shift of the lowest energy absorption band and phosphorescence band, as expected for low-energy excited states of the intraligand/metal-to-ligand charge transfer character. However, in addition to these conventional spectral shifts, another, at first unexpected, substitution effect occurs. Pt-thpy complexes 3 and 4 are dual emissive showing fluorescence about 6000 cm(-1) (∼0.75 eV) higher in energy relative to the phosphorescence band, while for Pt-ppy complexes 1 and 2 only phosphorescence is observed. For dual-emissive complexes 3 and 4, ISC rates kISC are estimated to be in order of 10(9)-10(10) s(-1), while kISC of Pt-ppy complexes 1 and 2 is much faster amounting to 10(12) s(-1) or more. The relative intensities of the fluorescence and phosphorescence signals of Pt-thpy complexes 3 and 4 depend on the excitation wavelength, showing that hyper-intersystem crossing (HISC) in these complexes is observably significant.
Collapse
Affiliation(s)
- Marsel Z Shafikov
- Ural Federal University , Mira 19, Ekaterinburg, 620002, Russia.,I. Postovsky Institute of Organic Synthesis , Ekaterinburg, 620041, Russia
| | | | | | | | | |
Collapse
|
18
|
Sieck C, Tay MG, Thibault MH, Edkins RM, Costuas K, Halet JF, Batsanov AS, Haehnel M, Edkins K, Lorbach A, Steffen A, Marder TB. Reductive Coupling of Diynes at Rhodium Gives Fluorescent Rhodacyclopentadienes or Phosphorescent Rhodium 2,2'-Biphenyl Complexes. Chemistry 2016; 22:10523-32. [PMID: 27355689 DOI: 10.1002/chem.201601912] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Indexed: 01/08/2023]
Abstract
Reactions of [Rh(κ(2) -O,O-acac)(PMe3 )2 ] (acac=acetylacetonato) and α,ω-bis(arylbutadiynyl)alkanes afford two isomeric types of MC4 metallacycles with very different photophysical properties. As a result of a [2+2] reductive coupling at Rh, 2,5-bis(arylethynyl)rhodacyclopentadienes (A) are formed, which display intense fluorescence (Φ=0.07-0.54, τ=0.2-2.5 ns) despite the presence of the heavy metal atom. Rhodium biphenyl complexes (B), which show exceptionally long-lived (hundreds of μs) phosphorescence (Φ=0.01-0.33) at room temperature in solution, have been isolated as a second isomer originating from an unusual [4+2] cycloaddition reaction and a subsequent β-H-shift. We attribute the different photophysical properties of isomers A and B to a higher excited state density and a less stabilized T1 state in the biphenyl complexes B, allowing for more efficient intersystem crossing S1 →Tn and T1 →S0 . Control of the isomer distribution is achieved by modification of the bis- (diyne) linker length, providing a fundamentally new route to access photoactive metal biphenyl compounds.
Collapse
Affiliation(s)
- Carolin Sieck
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Meng Guan Tay
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.,Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300, Kota Samarahan, Malaysia
| | | | - Robert M Edkins
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Karine Costuas
- Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS, Université de Rennes 1, 35042, Rennes Cedex, France
| | - Jean-François Halet
- Institut des Sciences Chimiques de Rennes, UMR 6226 CNRS, Université de Rennes 1, 35042, Rennes Cedex, France
| | - Andrei S Batsanov
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK
| | - Martin Haehnel
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Katharina Edkins
- School of Medicine, Pharmacy and Health, Durham University, University Boulevard, Stockton-on-Tees, TS17 6BH, UK
| | - Andreas Lorbach
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Andreas Steffen
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK
| | - Todd B Marder
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany. .,Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
| |
Collapse
|
19
|
Campos J, López-Serrano J, Peloso R, Carmona E. Methyl Complexes of the Transition Metals. Chemistry 2016; 22:6432-57. [PMID: 26991740 DOI: 10.1002/chem.201504483] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Indexed: 01/11/2023]
Abstract
Organometallic chemistry can be considered as a wide area of knowledge that combines concepts of classic organic chemistry, that is, based essentially on carbon, with molecular inorganic chemistry, especially with coordination compounds. Transition-metal methyl complexes probably represent the simplest and most fundamental way to view how these two major areas of chemistry combine and merge into novel species with intriguing features in terms of reactivity, structure, and bonding. Citing more than 500 bibliographic references, this review aims to offer a concise view of recent advances in the field of transition-metal complexes containing M-CH3 fragments. Taking into account the impressive amount of data that are continuously provided by organometallic chemists in this area, this review is mainly focused on results of the last five years. After a panoramic overview on M-CH3 compounds of Groups 3 to 11, which includes the most recent landmark findings in this area, two further sections are dedicated to methyl-bridged complexes and reactivity.
Collapse
Affiliation(s)
- Jesús Campos
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
| | - Joaquín López-Serrano
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain
| | - Riccardo Peloso
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain
| | - Ernesto Carmona
- Instituto de Investigaciones Químicas (IIQ), Departamento de Química Inorgánica and Centro de Innovación en Química, Avanzada (ORFEO-CINQA), Universidad de Sevilla and Consejo Superior de Investigaciones Cientificas (CSIC), Avenida Américo Vespucio 49, 41092, Sevilla, Spain.
| |
Collapse
|
20
|
Abstract
The emission from transition metal complexes is usually produced from triplet excited states. Owing to strong spin-orbit coupling (SOC), the fast conversion of singlet to triplet excited states via intersystem crossing (ISC) is facilitated. Hence, in transition metal complexes, emission from singlet excited states is not favoured. Nevertheless, a number of examples of transition metal complexes that fluoresce with high intensity have been found and some of them were even comprehensively studied. In general, three common photophysical characteristics are used for the identification of fluorescent emission from a transition metal complex: emission lifetimes on the nanosecond scale; a small Stokes shift; and intense emission under aerated conditions. For most of the complexes reviewed here, singlet emission is the result of ligand-based fluorescence, which is the dominant emission process due to poor metal-ligand interactions leading to a small metal contribution in the excited states, and a competitive fluorescence rate constant when compared to the ISC rate constant. In addition to the pure fluorescence from metal complexes, another two types of fluorescent emissions were also reviewed, namely, delayed fluorescence and fluorescence-phosphorescence dual emissions. Both emissions also have their respective unique characteristics, and thus they are discussed in this perspective.
Collapse
Affiliation(s)
- Y Y Chia
- Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia.
| | | |
Collapse
|
21
|
Nitsch J, Kleeberg C, Fröhlich R, Steffen A. Luminescent copper(i) halide and pseudohalide phenanthroline complexes revisited: simple structures, complicated excited state behavior. Dalton Trans 2015; 44:6944-60. [DOI: 10.1039/c4dt03706e] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Despite their chemical simplicity, copper(i) phenanthroline halides appear to involve multiple states in the emission process and exhibit non-trivial photophysical properties.
Collapse
Affiliation(s)
- Jörn Nitsch
- Institut für Anorganische Chemie
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Christian Kleeberg
- Institut für Anorganische und Analytische Chemie
- Technische Universität Carolo-Wilhelmina zu Braunschweig
- 38106 Braunschweig
- Germany
| | - Roland Fröhlich
- Organisch-Chemisches Institut
- Westfälische Wilhelms-Universität Münster
- 48149 Münster
- Germany
| | - Andreas Steffen
- Institut für Anorganische Chemie
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| |
Collapse
|
22
|
Steffen A, Costuas K, Boucekkine A, Thibault MH, Beeby A, Batsanov AS, Charaf-Eddin A, Jacquemin D, Halet JF, Marder TB. Fluorescence in Rhoda- and Iridacyclopentadienes Neglecting the Spin–Orbit Coupling of the Heavy Atom: The Ligand Dominates. Inorg Chem 2014; 53:7055-69. [DOI: 10.1021/ic501115k] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Andreas Steffen
- Institut
für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Karine Costuas
- Institut
des Sciences Chimiques de Rennes, UMR 6226 CNRS - Université de Rennes 1, 35042 Rennes Cedex, France
| | - Abdou Boucekkine
- Institut
des Sciences Chimiques de Rennes, UMR 6226 CNRS - Université de Rennes 1, 35042 Rennes Cedex, France
| | | | - Andrew Beeby
- Department
of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Andrei S. Batsanov
- Department
of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Azzam Charaf-Eddin
- CEISAM, UMR CNRS 6230, Université de Nantes, 2 rue de la
Houssinière, 44322 Nantes Cedex 3, France
| | - Denis Jacquemin
- CEISAM, UMR CNRS 6230, Université de Nantes, 2 rue de la
Houssinière, 44322 Nantes Cedex 3, France
- Institut Universitaire de France, 103 bd Saint-Michel, 75005 Paris Cedex 05, France
| | - Jean-François Halet
- Institut
des Sciences Chimiques de Rennes, UMR 6226 CNRS - Université de Rennes 1, 35042 Rennes Cedex, France
| | - Todd B. Marder
- Institut
für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Department
of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| |
Collapse
|