Ligand‐to‐Metal Charge Transfer (LMCT) Photochemistry at 3d‐Metal Complexes: An Emerging Tool for Sustainable Organic Synthesis

ChemCatChem, Год журнала: 2022, Номер 14(19)

Опубликована: Авг. 11, 2022

Abstract Despite the rich photochemistry of 3d‐metal complexes, utilization excited‐state reactivity these compounds in organic synthesis has been historically overlooked. The advent photoredox catalysis changed perception synthetic chemists towards photochemistry, and nowadays potential photoinduced, outer‐sphere single‐electron transfer events is widely recognized. More recently, an emerging new mode photoactivation taken spotlight, based on inner‐sphere triggered by population ligand‐to‐metal charge‐transfer (LMCT) excited states. Contrarily to photoredox, LMCT‐activation does not rely matching redox potentials, offers unique profiles particularly well suited Earth‐abundant metal complexes. Those appealing features are propelling development methods using this blueprint generate highly reactive open‐shell species under mild conditions. aim contribution provide a didactical tool for comprehension concept facilitate methodologies achieve sustainable chemical transformations.

Язык: Английский

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Luminescent First-Row Transition Metal Complexes

JACS Au, Год журнала: 2021, Номер 1(11), С. 1860 - 1876

Опубликована: Сен. 24, 2021

Precious and rare elements have traditionally dominated inorganic photophysics photochemistry, but now we are witnessing a paradigm shift toward cheaper more abundant metals. Even though emissive complexes based on selected first-row transition metals long been known, recent conceptual breakthroughs revealed that much broader range of in different oxidation states useable for this purpose. Coordination compounds V, Cr, Mn, Fe, Co, Ni, Cu show electronically excited with unexpected reactivity photoluminescence behavior. Aside from providing compact survey the key advances dynamic field, our Perspective identifies main design strategies enabled discovery fundamentally new types 3d-metal-based luminophores photosensitizers operating solution at room temperature.

Язык: Английский

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Luminescent and Photofunctional Transition Metal Complexes: From Molecular Design to Diagnostic and Therapeutic Applications

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(32), С. 14420 - 14440

Опубликована: Авг. 4, 2022

There has been emerging interest in the exploitation of photophysical and photochemical properties transition metal complexes for diagnostic therapeutic applications. In this Perspective, we highlight major recent advances development luminescent photofunctional complexes, particular, those rhenium(I), ruthenium(II), osmium(II), iridium(III), platinum(II), as bioimaging reagents phototherapeutic agents, with a focus on molecular design strategies that harness modulate interesting behavior complexes. We also discuss current challenges future outlook both fundamental research clinical

Язык: Английский

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Phototherapeutic anticancer strategies with first-row transition metal complexes: a critical review

Chemical Society Reviews, Год журнала: 2022, Номер 51(3), С. 1167 - 1195

Опубликована: Янв. 1, 2022

This review presents an up-to-date state of the art on first-row-transition metal complexes, from titanium to zinc, in regard their applications as photosensitisers for phototherapeutic applications.

Язык: Английский

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Long Persistent Luminescence from Metal–Organic Compounds: State of the Art

Advanced Functional Materials, Год журнала: 2023, Номер 33(19)

Опубликована: Март 18, 2023

Abstract The excited‐state tuning of luminescent metal–organic compounds has made great progress in the fields optical imaging, photocatalysis, photodynamic therapy, light‐emitting devices, sensors, and so on. Although with high luminescence efficiency can be realized via enhanced molecular rigidity heavy‐atom effect, their corresponding lifetimes are still limited on order a nanosecond to millisecond, owing inherent competition between luminous lifetime. Therefore, advanced applications (i.e., persistent afterglow information security, anti‐counterfeiting, smart materials, among others) related long (LPL, typically lifetime larger than millisecond) seriously hindered. This review gives timely systematic summary for realizing room‐temperature phosphorescence (RTP)‐type thermally activated delayed fluorescence (TADF)‐type LPL during last few years. Particularly, based perspectives time, space, energy dimensions, fundamental materials design coordination assembly systematically described first time. Moreover, internal external factors influencing properties terms efficiency, lifetime, color illustrated. Last but not least, challenges also discussed developing from compounds.

Язык: Английский

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Manganese(i) complexes with metal-to-ligand charge transfer luminescence and photoreactivity

Nature Chemistry, Год журнала: 2021, Номер 13(10), С. 956 - 962

Опубликована: Авг. 2, 2021

Язык: Английский

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Iron Photoredox Catalysis–Past, Present, and Future

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(17), С. 9369 - 9388

Опубликована: Апрель 20, 2023

Photoredox catalysis of organic reactions driven by iron has attracted substantial attention throughout recent years, due to potential environmental and economic benefits. In this Perspective, three major strategies were identified that have been employed date achieve reactivities comparable the successful noble metal photoredox catalysis: (1) Direct replacement a center in archetypal polypyridyl complexes, resulting metal-centered photofunctional state. (2) situ generation photoactive complexes substrate coordination where are via intramolecular electron transfer involving charge-transfer states, for example, through visible-light-induced homolysis. (3) Improving excited-state lifetimes redox potentials states new ligand design. We seek give an overview evaluation developments rapidly growing field and, at same time, provide outlook on future iron-based catalysis.

Язык: Английский

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Photoactive Metal-to-Ligand Charge Transfer Excited States in 3d⁶ Complexes with Cr⁰, Mn^I, Fe^II, and Co^III

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(9), С. 4903 - 4920

Опубликована: Фев. 21, 2023

Many coordination complexes and organometallic compounds with the 4d6 5d6 valence electron configurations have outstanding photophysical photochemical properties, which stem from metal-to-ligand charge transfer (MLCT) excited states. This substance class makes extensive use of most precious least abundant metal elements, consequently there has been a long-standing interest in first-row transition photoactive MLCT Semiprecious copper(I) its completely filled 3d subshell is relatively straightforward well explored case, but 3d6 partially d-orbitals lead to energetically low-lying metal-centered (MC) states that can cause undesirably fast state deactivation. Herein, we discuss recent advances made isoelectronic Cr0, MnI, FeII, CoIII compounds, for long-lived become accessible over past five years. Furthermore, possible future developments search new subshells next-generation applications photophysics photochemistry.

Язык: Английский

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Spin-flip luminescence

Photochemical & Photobiological Sciences, Год журнала: 2022, Номер 21(7), С. 1309 - 1331

Опубликована: Март 5, 2022

Abstract In molecular photochemistry, charge-transfer emission is well understood and widely exploited. contrast, luminescent metal-centered transitions only came into focus in recent years. This gave rise to strongly phosphorescent Cr III complexes with a d 3 electronic configuration featuring excited states which are characterized by the flip of single spin. These so-called spin-flip emitters possess unique properties require different design strategies than traditional phosphors. this review, we give brief introduction ligand field theory as framework understand phenomenon outline prerequisites for efficient including strength, symmetry, intersystem crossing common deactivation pathways using instructive examples. The progress associated challenges tuning energies emissive emerging applications photophysical discussed. Finally, summarize current state-of-the-art beyond 2 , 4 8 configuration, where mainly cover pseudooctahedral V, Mo, W, Mn, Re Ni, highlight possible future research opportunities. Graphical abstract

Язык: Английский

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Photoredox-active Cr(0) luminophores featuring photophysical properties competitive with Ru(II) and Os(II) complexes

Nature Chemistry, Год журнала: 2023, Номер 15(12), С. 1730 - 1736

Опубликована: Авг. 14, 2023

Coordination complexes of precious metals with the d6 valence electron configuration such as Ru(II), Os(II) and Ir(III) are used for lighting applications, solar energy conversion photocatalysis. Until now, made from abundant first-row transition competitive photophysical photochemical properties have been elusive. While previous research efforts focused mostly on Fe(II), we disclose that isoelectronic Cr(0) gives access to higher photoluminescence quantum yields excited-state lifetimes when compared any other metal complex reported so far. The luminescence behaviour metal-to-ligand charge transfer excited states these is polypyridines. With complexes, become exploitable in photoredox catalysis, benchmark chemical reductions proceed efficiently under low-energy red illumination. Here demonstrate appropriate molecular design strategies open up new perspectives photophysics photochemistry metals.

Язык: Английский

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