Exploring and leveraging aggregation effects on reactive oxygen species generation in photodynamic therapy

Aggregate, Год журнала: 2024, Номер 5(4)

Опубликована: Март 10, 2024

Abstract Aggregate‐level photodynamic therapy (PDT) has attracted significant interest and driven substantial advances in multifunction phototheranostic platforms. As exemplified by two typical instances of aggregation‐caused quenching reactive oxygen species (ROS) aggregation‐induced generation ROS, the aggregation effect plays a role on ROS photosensitizers (PSs), which is worthy in‐depth exploration full utilization. However, contrast to well‐developed researches luminescence, studies concerning are currently relatively nascent disjointed stage, lacking guidance from firmly established research paradigm. To advance this regard, review aims at providing consolidated overview fundamental principles status effects generation. Here, can be organized into main facets. One involves comparison between isolated state aggregated state, mainly conducted methods changing solvent environments adding adjuvants given solvent. The other underscores distinctions different aggregate states, consisting three parts, namely within same or categories based classification single‐component multicomponent aggregates. In endeavor, we will present our views current methodologies that explore how affects highlight design strategies leverage optimize PS regiments. We aspire propel advancement platforms accelerate clinical implementation precision medicine, inspire more contributions aggregate‐level photophysics photochemistry, pushing science materials forward.

Язык: Английский

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Ligand Exchange at Carbon: Synthetic Entry to Elusive Species and Versatile Reagents

JACS Au, Год журнала: 2024, Номер 4(5), С. 1709 - 1722

Опубликована: Апрель 15, 2024

How different is carbon compared to other elements in the periodic table? Can compounds be regarded as coordination complexes with central element undergoing a facile exchange of its ligands? Although clearly plays special role among table, recent studies have drawn parallels between bonding situation and reactivity transition metal complexes. This Perspective summarizes reports about ylidic zwitterionic that were shown exhibit ambiguous situations can interpreted donor–acceptor interactions similar bond neutral ligand. Based on this conception, ligand reactions prototypical realized at atoms, enabling new synthetic strategies for synthesis reactive species building blocks. In particular, N2, CO, phosphine ligands led development mild method accessing reagents unusual properties, such vinylidene ketenes or stable ketenyl anions, open up diverse but still poorly explored follow-up chemistry.

Язык: Английский

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Lewis Superacidic Heavy Pnictaalkene Cations: Comparative Assessment of Carbodicarbene-Stibenium and Carbodicarbene-Bismuthenium Ions

Inorganic Chemistry, Год журнала: 2022, Номер 61(46), С. 18640 - 18652

Опубликована: Ноя. 9, 2022

We report a comprehensive assessment of Lewis acidity for series carbone-stibenium and -bismuthenium ions using the Gutmann-Beckett (GB) method. These new antimony bismuth cations have been synthesized by halide abstractions from (CDC)PnBr3 [(pyCDC)PnBr2][Br] (CDC = carbodicarbene; Pn Sb or Bi; py pyridyl). The reaction (CDC)SbBr3 (1) with one two equivalents AgNTf2 (NTf2 bis(trifluoromethanesulfonyl)imide) AgSbF6 gives stibaalkene mono- dications form [(CDC)SbBr3-n][A]n (2-4; n 1,2; A NTf2 SbF6). trication [(CDC)2Sb][NTf2]3 (5) was also isolated collectively these molecules fill gap among cationic pnictaalkenes. are compared to related CDC-bismaalkene complexes 6-9. With goal preparing highly acidic compounds, tridentate bis(pyridine)carbodicarbene (pyCDC) used as ligand access (10, 12) trications [(pyCDC)Pn][NTf2]3 (Pn (11), Bi (13)), forgoing need second CDC in synthesis 5. bonding situation is elucidated through electron density energy decomposition analyses combination natural orbital chemical valence theory. In each complex, there exists CDC-Pn double interaction, consisting strong σ-bond weaker π-bond, whereby π-bond gradually strengthens increase charge complex. Notably, [(CDC)SbBr][NTf2]2 (4) has an acceptor number (AN) (84) that comparable quintessential acids such BF3, tricationic pnictaalkene 11 13 exhibit ANs 109 Sb) 84 Bi), respectively, which highest values reported any cation. Moreover, calculated fluoride ion affinities (FIAs) 99.8 94.3 kcal/mol, larger than SbF5 (85.1 kcal/mol), suggest superacids.

Язык: Английский

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A Borenium-Borane Composite for Exhaustive Reduction of Oxo-Chemicals

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 2, 2025

Borenium ions have attracted significant attention in organic transformations due to their strong Lewis acidity. The reported borenium are often stabilized by sterically demanding substituents and coordination bonds. Herein, we synthesized a small steric borenium-equivalent NH3BH2OTf subjected it the exhaustive reduction of carboxylic functional group methyl group, which shows broad tolerance. This system can also undergo reductive deoxygenation reaction alcohols, ethers, other oxo-chemicals (>100 examples). mechanistic studies revealed that situ-generated NH3BH2OTf/[NH3BH2(sol)]OTf, rendering borenium-like properties, plays crucial role these interacting with O atom substrates activate carbonyl facilitating cleavage C–O bond. work has not only offered for but is great significance providing insight into application various reactions.

Язык: Английский

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Access to Bis-Silylene-Stabilized Group 13 Cations

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 6, 2025

Herein, we report the isolation of pyridine moiety-functionalized SiNSi pincer-based bis-silylene ligand (1) and its reactivity toward various halide precursors (X = Br I) group 13 elements (M Al, Ga, In). This gave us straightforward access to pincer-coordinated cations (2–7). These complexes are duly characterized by single-crystal X-ray diffraction studies, multinuclear magnetic resonance spectroscopy (1H, 13C, 29Si), high-resolution mass spectrometry techniques. Their electronic properties were further analyzed with help quantum chemical calculations.

Язык: Английский

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Air- and photo-stable luminescent carbodicarbene-azaboraacenium ions

Nature Chemistry, Год журнала: 2023, Номер 16(3), С. 437 - 445

Опубликована: Дек. 5, 2023

Язык: Английский

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Synthesis, Characterization, and Properties of Three-Dimensional Analogues of 9-Borafluorenes

Inorganic Chemistry, Год журнала: 2022, Номер 61(45), С. 18275 - 18284

Опубликована: Ноя. 4, 2022

Three-dimensional (3D) analogues of 9-borafluorenes, (C2B10H10)2BR (R = Cl (1), Br (2), H (3, merely as ether or silane adduct), phenyl (4), mesityl (5)), were synthesized and fully characterized. Gutmann–Beckett computational fluoride/hydride ion affinity (FIA/HIA) studies confirmed the Lewis superacidity 1–4, with acidity 1–3 being higher than that corresponding 3D 9,10-diboraanthracenes (DBA). The group C4B borole unit are nearly coplanar in solid state, while rotation 5 is hindered, forcing to adopt a large C4B/Mes dihedral angle, which leads distinct properties: air-stable bluish-violet fluorescence arising from intramolecular charge-transfer (ICT) transition. 29Si NMR spectra indicated high silylium cation character 3·Et3SiH. reaction 4 Ph3CBr yielded (Ph3C)+[(C2B10H10)2B(Ph)Br]− (6). 4/PPh3 pair was capable splitting dihydrogen Si–H bond triethylsilane.

Язык: Английский

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Synthesis and Reactivity of an Anionic Diazoolefin

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(34)

Опубликована: Июнь 30, 2023

Abstract Bent (hetero)allenes such as carbodicarbenes and carbodiphosphoranes can act neutral C‐donor ligands, diverse applications in coordination chemistry have been reported. N‐Heterocyclic diazoolefins are heterocumulenes, which function a similar fashion L‐type ligands. Herein, we describe the synthesis reactivity of an anionic diazoolefin. This compound displays distinct compared to diazoolefins, evidenced by preparation diazo compounds via protonation, alkylation, or silylation. The diazoolefin be employed ambidentate, X‐type ligand salt metathesis reactions with metal halide complexes. Extrusion dinitrogen was observed reaction PCl(N i Pr 2 ) , resulting stable phosphinocarbene.

Язык: Английский

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Redox- and Charge-State Dependent Trends in 5, 6, and 7-Membered Boron Heterocycles: A Neutral Ligand Coordination Chemistry Approach to Boracyclic Cations, Anions, and Radicals

Accounts of Chemical Research, Год журнала: 2024, Номер 57(10), С. 1510 - 1522

Опубликована: Май 6, 2024

ConspectusBoron heterocycles represent an important subset of heteroatom-incorporated rings, attracting attention from organic, inorganic, and materials chemists. The empty pz orbital at the boron center makes them stand out as quintessential Lewis acidic molecules, also serving a means to modulate electronic structure photophysical properties in facile manner. As boracycles are ripe for extensive functionalization, they used catalysis, chemical biology, science, continue be explored synthons conjugated reagents. Neutral boron(III)-incorporated polycyclic molecules some most studied types boracycles, understanding their redox transformations is applications relying on electron transfer charge transport. While relevant species can often electrochemically observed, it remains challenging isolate characterize where and/or skeleton have been chemically reduced.We describe our recent work isolating 5-, 6-, 7-membered boracyclic radicals, anions, cations, focusing stabilization strategies, ligand-mediated bonding situations, reactivity. We present versatile neutral ligand coordination chemistry approach that permits transformation potent electrophiles powerful nucleophilic facilitate diverse bond activation chemistry. Although there wide range suitable stabilizing ligands, we employed both diamino-N-heterocyclic carbenes (NHCs) cyclic(alkyl)(amino) (CAACs), which led with tunable structures aromaticity trends. highlight successful isolation borafluorene radicals demonstrate reversible behavior, undergoing oxidation cation or reduction anion. anion synthon has prepare boryl main-group transition-metal bonds, luminescent oxabora-spirocycles, borafluorenate-crown ethers, CO-releasing via carbon dioxide activation. expanded 6-membered characterized bis(NHC-supported 9-boraphenanthrene)s corresponding bis(CAAC-stabilized 9-boraphenanthrene) biradical. detail interconvertible multiredox states boraphenalene, boraphenalenyl radical, anion, mimic charge-states all-hydrocarbon analogue. Reactivity studies displayed unusual reactivity multiple sites periphery tricyclic scaffold. Reduced borepins, containing heterocycles, isolated. stepwise one-pot synthesis combining halo-borepin precursor, CAAC, KC8 afford monomeric borepin anions. π-system was extended contain two rings fused pentacyclic scaffold, permitted diborepin biradicals dibora-quinone core.Our goal provide guide explaining current structure–function trends strategies redox-active boron-incorporated initiate rational design use these compounds across vast space.

Язык: Английский

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The emergence of zerovalent carbon compounds from structural curiosities to organocatalysts

Cell Reports Physical Science, Год журнала: 2023, Номер 4(8), С. 101519 - 101519

Опубликована: Июль 31, 2023

Low-valent main group compounds have reactivity patterns and properties reminiscent of transition metals. While divalent carbon such as carbenes are widely studied ligands organocatalysts, zerovalent species received considerably less attention. This perspective highlights the compounds, focusing on their first applications organocatalysts for small molecule reduction polymerization reactions.

Язык: Английский

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