Publications by authors named "Shunyou Cai"

High-temperature phosphorescence (HTP) materials have attracted considerable attention owing to their expanded application prospects, whereas they still suffer from severe deactivation in polar media, limiting their reliability and utility. Here, we present an efficient multivalent assembly strategy to achieve high-temperature liquid-phase phosphorescence (HTLP). The supramolecular assembly of multivalent modules leads to extremely robust hydrogen-bonding networks, which firmly immobilize the organic phosphors and protect triplet excitons from annihilation in high-temperature polar media, resulting in excellent HTLP emission.

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We have effectively utilized cost-effective 2-bromoanthraquinone as a photocatalyst to develop an efficient and environmentally friendly method for producing -hydroxy lactones under mild visible light irradiation. Importantly, this protocol only relies on oxygen as an oxidant, completely eliminating the need for additional chemical reagents and showcasing a sustainable approach to chemical transformation. Operating at room temperature, we utilized a mixed solvent system of DMF and CHCl, which greatly facilitated the selective conversion of various 2-vinylbenzoic acids and carboxylic acids to functional -hydroxyl lactones.

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The type of coordinated N atoms in the metal-N coordination structure is of paramount importance to the catalytic property of N-modified carbon-based single-atom catalysts (SACs). Extended X-ray absorption fine structure (EXAFS) spectroscopy is a powerful tool for analyzing the coordination environments of SACs. Despite its efficacy, the limited availability of synchrotron light sources and the complexity of data analysis have constrained its broader application in identifying metal-N coordination types within SACs.

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Room-temperature phosphorescent carbon dots (RTP-CDs) have received increasing attention due to their excellent optical properties and potential applications. Nevertheless, the realization of RTP-CDs in aqueous solutions remains a considerable challenge due to the water-molecule- and oxygen-induced deactivation of the triplet excitons, which leads to phosphorescence quenching. In this study, ultralong phosphorescence in water was achieved by in situ self-assembly of CDs encapsulated in a rigid hydrogen-bonded organic framework (HOF).

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Electrochemiluminescence (ECL) featuring thermally activated delayed fluorescence (TADF) properties has attracted considerable interest, showcasing their potential for 100 % exciton harvesting, which marks a significant advancement in the realm of organic ECL. However, the challenge of elucidating the precise contribution of TADF to the enhanced ECL efficiency arises due to the lack of comparative studies of organic compounds with or without efficient TADF properties. In this study, we present four carbazole-benzonitrile molecules possessing similar chemical structures and comparable exchange energy (ΔE).

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A rational combination of photoredox catalyst anthraquinone and hydrogen atom transfer (HAT) catalyst methyl thioglycolate allows for the rapid and straightforward conversion of a range of 2-amidated acetylenic alcohols to multifunctional ,-spirocycles under visible light irradiation. With oxygen as the sole terminal oxidant, these reactions can be carried out efficiently at room temperature without the involvement of transition metals or strong oxidants. The successful application of this mild catalytic strategy in the late-stage functionalization of bioactive skeletons further highlights its practical value.

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Catalytic C(sp)-H functionalization has afforded great opportunities to prepare organic substances, facilitating the derivatization of complex drugs and natural molecules. This letter describes an efficient and practical protocol for lanthanum-catalyzed continuous epoxy-ring opening and oxidative dehydrogenative lactonization under visible-light irradiation. Notably, the lanthanum catalyst also acts as a photocatalyst while acting as a Lewis acid in this reaction; therefore, no additional photocatalyst is required.

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Direct functionalization of inert C(sp)-H bonds is an attractive synthetic technology for the preparation of pharmaceutically significant compounds in modern synthetic organic chemistry. In this work, we report a new method for the synthesis of functionalized benzocoumarins through the strategy of activation of multiple C-H bonds on 2-aryl toluenes under visible-light-enabled photoredox conditions. This method has the advantages of high functional group compatibility, mild reaction conditions, and effectively avoiding the use of strong oxidants and precious metal catalysts.

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Glucosamine hydrochloride (GAH), one of the most basic and important derivatives of chitin, is obtained by hydrolysis of chitin in concentrated hydrochloric acid. At present, little is known about how GAH functions in skeletal development. In this report, we demonstrate that GAH, extracted from the cell wall of , acts in a dose-dependent manner to promote not only cartilage and bone development in larvae but also caudal fin regeneration in adult fish.

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A practical and direct method for oxidative cross-coupling of alkenes with dialkylformamides is established employing visible-light-enabled photoredox catalysis. This strategy allows efficient access to diverse unsaturated amides under mild reaction conditions. The application of an appropriate diaryliodonium salt was demonstrated to be critical to the success of this process.

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Oxidative cross-coupling reactions of benzyl alcohols with N,N-dialkylacetamides were developed only employing oxygen as the terminal oxidant, efficiently providing a new, novel protocol for the construction of multifunctionalized cinnamides with the synergistic effects of KOH, organic photocatalyst eosin Y, and visible light irradiation at room temperature. A broad substrate scope and mild reaction conditions are the prominent features of this transformation.

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Metal-free oxidative radical 1,2-alkylarylation of unactivated alkenes with the α-C(sp)-H bond of dimethyl sulfoxide has been developed. This study realizes a new, conceptually novel technology for convenient construction of a variety of α-aryl-γ-methylsulfinyl ketones in good-to-excellent yields with the synergistic interactions of visible light irradiation, organic fluorophores 4CzIPN, and hypervalent iodine(III) reagent under transition-metal free conditions. A remarkable kinetic isotope effect was observed, which helped provide insight into the reaction's mechanistic course.

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Mild and direct intramolecular oxidative aryltrifluoromethylations of activated alkenes have been established through visible light photocatalysis, affording a range of CF3-containing oxindoles or isoquinolinediones in the presence of an organic fluorophore-type photocatalyst 4CzIPN, oxygen and visible light irradiation under strong oxidant and transition metal free conditions. A variety of frequently encountered functional groups are well tolerated in this transformation.

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Aging of secondary organic aerosol (SOA) particles formed from OH- initiated oxidation of ethylbenzene in the presence of high mass (100-300μg/m(3)) concentrations of (NH4)2SO4 seed aerosol was investigated in a home-made smog chamber in this study. The chemical composition of aged ethylbenzene SOA particles was measured using an aerosol laser time-of-flight mass spectrometer (ALTOFMS) coupled with a Fuzzy C-Means (FCM) clustering algorithm. Experimental results showed that nitrophenol, ethyl-nitrophenol, 2,4-dinitrophenol, methyl glyoxylic acid, 5-ethyl-6-oxo-2,4-hexadienoic acid, 2-ethyl-2,4-hexadiendioic acid, 2,3-dihydroxy-5-ethyl-6-oxo-4-hexenoic acid, 1H-imidazole, hydrated N-glyoxal substituted 1H-imidazole, hydrated glyoxal dimer substituted imidazole, 1H-imidazole-2-carbaldehyde, N-glyoxal substituted hydrated 1H-imidazole-2-carbaldehyde and high-molecular-weight (HMW) components were the predominant products in the aged particles.

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Decarboxylative cross-coupling reactions of cinnamic acids with sulfonylhydrazides were explored using oxygen as the sole terminal oxidant, realizing a conceptually novel technology for vinyl sulfone synthesis under the synergistic interactions of visible light irradiation, organic dye-type photocatalyst eosin Y, KI, and Cs2CO3 at room temperature.

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A variety of functionalized β-keto sulfones were smoothly prepared through oxysulfonylation of commercially available alkynes with sulfonylhydrazides under the synergistic interactions of visible light irradiation, Ru(bpy)3Cl2 photocatalyst, oxygen, KI, and NaOAc basic additive under very mild reaction conditions.

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A judicious combination of Au-catalysis and synergistic visible-light stimulation formulates an exceptionally simple and mild reaction system capable of directly coupling anilines and alkynes to form multifunctionalized indoles.

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A range of nitro compounds are smoothly reduced to their corresponding oximes under the synergistic effects of visible light irradiation, the Ru(bpy)3Cl2 photocatalyst, Hünig's base, Mg(ClO4)2 activation, and MeCN solvent. This remarkably mild and environmentally benign protocol, when orchestrated with classical Beckmann rearrangement, enables such high-value industrial feedstock as caprolactam to be readily accessed from simple precursor nitrocyclohexane.

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Remarkable Ag-carbenoid-initiated enone cyclopropanation-hydrolytic fragmentation-competitive 1,2-vs-1,4 addition reaction cascades were uncovered on a range of propargylic esters tethered to cyclohexadienones, leading to the highly efficient and stereospecific construction of densely functionalized bicyclo[3.3.1]nonanes under mild conditions.

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