A photoinduced radical difunctionalization of alkenes with Na2S2O5, aryl thianthrenium salts, and H2O to construct β-hydroxysulfones is reported. The reaction proceeds under mild conditions with a broad substrate scope and excellent functional group compatibility, including late-stage modification of drug-like molecules. EPR studies support a radical pathway involving visible-light-induced generation of the aryl radical from thianthrenium salt followed by sulfur dioxide insertion to form the sulfonyl radical intermediate.

In recent years, a photoredox catalysis strategy has emerged as a powerful platform for generating open-shell intermediates under mild conditions, enabling the development of novel radical-based transformations that are difficult to achieve via traditional ionic pathways. Among these, radical-mediated cyclization reactions allow for the rapid and modular assembly of complex molecular scaffolds. Herein, we report a visible-light-driven formal [3 + 2] cycloaddition reaction of electron-deficient 1,3-conjugated enynes and α-silylamines. This reaction provides a practical route to highly functionalized 2,3-dihydropyrroles under mild and redox-neutral conditions with operational simplicity and a broad substrate scope.

Abstract The direct conversion of abundant alkanes and unactivated indoles into valuable 2-alkylindolines remains a challenging transformation in synthetic organic chemistry. Herein, we report a visible-light-induced, iron-catalyzed radical dearomative hydroalkylation of free (NH)-indoles with simple alkanes. Using inexpensive FeCl3 as the photocatalyst, this protocol provides a direct and step-economical route to a range of C2-alkylated indolines in good to excellent yields. Mechanistically, the reaction proceeds via LMCT-triggered chlorine radical-mediated hydrogen atom transfer (HAT) from alkanes, followed by C2-selective radical addition to an acid-promoted iminium tautomer. This work establishes a practical platform for the synthesis of 2-alkylated indolines from simple feedstocks without the need for prefunctionalization.

Despite significant progress in two-electron asymmetric alpha-vinylation of carbonyl compounds with activated alkynes, extending this methodology to less reactive or unactivated alkynes remains challenging due to the polarity mismatch in these ionic processes. Herein, we report an efficient visible-light-induced direct asymmetric alpha-vinylation of beta-ketocarbonyls with commercially available simple alkynes by dual photoredox/nickel Lewis acid catalysis under hydrogen atom transfer (HAT) mediation. This transformation features the catalytic photogeneration of a chiral nickel-bound alpha-carbonyl radical that undergoes stereoselective addition to alkynes. The resulting vinyl radical species engages in a rapid HAT process with thiophenol (ArSH), ensuring high regioselectivity, stereoselectivity, and Z/E selectivity. This protocol circumvents the need for prefunctionalized vinyl reagents, exhibits broad functional group tolerance, and provides efficient access to enantioenriched alkenes bearing all-carbon quaternary stereocenters.

To develop high-performance iridium phosphorescent complexes, we designed and synthesized a series of iridium phosphorescent complexes (G-1, G-2, B-1, B-2, R-1, R-2) using 3-hydroxy-2-methyl-4-pyrone (maltol, short for mal) and 3-hydroxy-2-ethyl-4-pyrone (ethyl maltol, short for emal) as auxiliary ligands, in combination with 2-phenylpyridine (ppy), 2-(2,4-difluorophenyl)pyridine (dfppy), and 1-phenylisoquinoline (piq) as cyclometalating ligands. We systematically investigated their crystal structures, photophysical behavior, electrochemical properties, and electroluminescent performance. The results revealed that the combination of a pyranone auxiliary ligand with the highly conjugated piq ligand leads to the formation of R-1 and R-2, which possess high molecular symmetry and display favorable photophysical performance. These complexes exhibit solution-phase phosphorescence quantum yields of 64% and 55%, and electroluminescent devices incorporating them reach a maximum external quantum efficiency of 13.4%, with brightness exceeding 13,000 cd/m2 and minimal efficiency roll-off. In contrast, complexes incorporating pyridine-based cyclometalating ligands (ppy, dfppy)—G-1, G-2, B-1, and B-2—display weak emission in solution but show enhanced solid-state emission through π–π stacking, with a maximum quantum yield of 25.8%. Density functional theory calculations and electrochemical analysis indicate that the presence of both the pyranone auxiliary ligand and the piq ligand results in optimized frontier orbital energy alignment, enhanced metal-to-ligand charge transfer, and reduced non-radiative transitions, thereby improving emission efficiency. This study provides a theoretical framework and molecular design strategy for the application of pyranone auxiliary ligands in high-performance iridium phosphorescent materials.

Chloride-free platinum precursors for diesel oxidation catalysts (DOCs) must reconcile the conflicting requirements of low-temperature decomposition—to avoid Pt sintering during calcination—and exceptional hydrothermal durability, an inherent trade-off that conventional platinum precursors have not resolved. Here, we report two chloride-free Pt(IV) carboxylate complexes, trans-[Pt(NH₃)₄(OH)₂](CH3COO)₂ (Pt-L) and trans-[Pt(NH₃)₄(OH)₂](HOOCCH2COO)₂ (Pt-M), synthesized via a scalable salt-metathesis route. Single-crystal X-ray diffraction revealed that both complexes adopt distorted octahedral geometries with distinct crystal packing (triclinic P-1 for PtL and monoclinic P21/c for PtM), governed by extensive hydrogen-bonding networks. Thermogravimetric analysis demonstrated quantitative decomposition to metallic Pt below 300 °C (peaks at 235.7 °C for PtL and 268.1 °C for PtM), substantially lower than conventional chloride or nitrate analogues. When evaluated as DOCs (1.3 wt% Pt/Al₂O₃), PtM showed a counterintuitive performance trend. The fresh catalyst was less active for CO, C₃H₆ and NO oxidation than a commercial Pt(NO₃)₂-derived reference, but hydrothermal ageing at 700 °C for 10 h produced a striking reversal: the aged PtM/Al₂O₃ catalyst exhibited markedly lower temperatures than the aged reference. This improvement may be attributed to the monodentate hydrogen malonate anion, which mediates stronger precursor–support interactions that inhibit Pt nanoparticle sintering and stabilize the active phase under harsh conditions. These findings demonstrate that PtM overcomes the conventional calcination–stability dilemma and offers a viable chloride-free precursor for next-generation emission-control catalysts.

Organic light-emitting diodes (OLEDs) based on phosphorescent materials are among the most promising technologies for displays and lightings. For red-emitting heteroleptic iridium complexes (HICs), vast and major research has been focused on the design and synthesis of cyclometalated ligands, while relatively little attention has been given to ancillary ligands which also play important roles in manipulating the optoelectronic and electroluminescent properties of HICs. Seven deep red-emitting HICs were designed and synthesized by systematically modifying the alkyl groups in β-diketone-type ancillary ligands. These HICs exhibited similar physical and optoelectronic properties, with OLED devices based on these materials achieving consistent emission peaks at 624 nm and CIE coordinates of (0.68, 0.32). Among the synthesized HICs, Ir(dmippiq)₂(dmeacac), featuring 3,7-dimethyl-4,6-nonanedione as the ancillary ligand, demonstrated the best OLED performance, achieving a champion external quantum efficiency (EQE) of 18.26%. This result highlights that engineering the alkyl groups in β-diketone ancillary ligands can significantly enhance device performance.

A photoredox formal [4 + 2] cycloaddition reaction has been developed, which directly utilizes commercially available and affordable α-bromoketones and terminal alkynes to produce naphthol derivatives in a single step. This method features mild reaction conditions and straightforward operation. The naphthol derivatives obtained can be easily transformed into 4-substituted naphthols, 3-substituted benzofurans, and imidazo heterocycles.

Green-emitting iridium (III) complexes were synthesised using chlorobridged dimer(ppy)2Ir2Cl2(ppy)2, 3-hydroxy-2-methyl-γ-pyranone,2-ethyl-3-hydroxy-4-pyranone, and 5-hydroxy-2-(hydroxymethyl)-1,4-pyranone as the auxiliary ligand. The structure of the target product was characterised by nuclear magnetic resonance spectroscopy(1H-NMR), infrared spectroscopy(IR) and mass spectrometry(MS), and its thermal stability, photophysical properties and electrochemical properties were investigated. The results show that the decomposition temperatures of Ir1, Ir2 and Ir3 are 3 49, 292 and 200 °C, respectively. The maximum emission wavelength of Ir1, Ir2 and Ir3 dissolved in dichloromethane is 491 nm. The HOMO energy level of Ir1, Ir2 and Ir3 are 5.39, −5.38, and −5.30 eV. The LUMO energy levels are −2.86, −2.85, and −2.80 eV, respectively.

The reverse water-gas shift reaction has attracted significant attention as a promising solution for carbon neutrality. However, the inefficiency at low temperature restricts its progress in industrialization. In this study, we developed a high-performance PtFEc/CeO2 catalyst using a novel platinum precursor. This catalyst features fully exposed platinum (Pt) clusters that interact with CeO2, resulting in the formation of unique Pt delta+-O-Ce3+ active sites, which generate a substantial number of oxygen vacancies. The oxygen vacancy sites enhance the adsorption and activation of CO2. Moreover, the Pt delta+-O-Ce3+ sites not only facilitate the hydrogenation of CO2 by promoting hydrogen spillover from the Pt clusters to CeO2 but also reduce CO adsorption on Pt, aiding in CO release. With this synergistic interaction of dual active sites assistance, the PtFEc/CeO2 catalyst achieved a CO2 conversion of 29.2 % at 350 degrees C, approaching the thermodynamic equilibrium yield of CO2 (30.0 %). Additionally, the PtFEc/CeO2 catalyst displayed remarkable stability, maintaining its activity without noticeable deactivation for up to 550 h. This work offers a promising strategy for enhancing the efficiency of the RWGS reaction.

Two bis-cyclometalated heteroleptic iridium complexes incorporating 1-phenylisoquinoline (piq) as the main cyclometalating ligand and 3-hydroxy-2-methyl-4-pyrone (ma) or 2-ethyl-3-hydroxy-4H-pyran-4-one (ema) as the auxiliary ligand, namely Ir(piq)2(ma) (Ir-1) and Ir(piq)2(ema) (Ir-2), were developed and applied as deep-red phosphors in organic light-emitting diodes (OLEDs). The two auxiliary ligands had similar influences on the photophysical, electrochemical, and electroluminescent properties of the iridium complexes. Ir(piq)2(ma) (Ir-1) showed better luminescence performance in a simple phosphorescent OLED compared to the traditional red iridium complex Ir(piq)2(acac) and exhibited a current efficiency of 9.39 cd A−1 (EQE of 12.09%). In contrast, Ir(piq)2(ema) exhibited an efficiency of 8.6 cd A−1 (EQE of 10.19%).

A photoredox/nickel dual catalysis is presented for the construction of several kinds of useful nitrogen-containing heterocycles. This protocol is regioselective and features a broad substrate scope. It provides a direct access to nitrogen-containing heterocycles by reacting alkyl chlorides with readily available activated and unactivated alkenes. Moreover, this protocol can be easily scalable to a gram-scale, and it is feasible to use sunlight as the light source. Mechanistic studies suggest that the energy transfer pathway is involved in the catalytic process.

Phosphorescent iridium complexes are the electroluminescent materials with the best comprehensive performance. Phosphorescent iridium complexes have been employed in organic light-emitting diodes (OLEDs), electrochemical light-emitting cells (LECs), photocatalysis, tumour diagnosis and sensors owing to their various advantages such as high quantum efficiency, good thermal stability and tunable emission colors. The color tuning of the iridium phosphorescent complex can be realized by changing the chemical structure of the main ligands and auxiliary ligands such as changing the conjugation degree of ligand, electron-donating and with drawing ability of substituents and substituent position. The influence of substituent position on iridium phosphorescent complex's photophysical properties was rarely researched. In this paper, we propose studying the effect of different substitution positions of methyl groups on the photophysical properties of iridium phosphorescent complexes. Two new iridium phosphorescence complexes (2,4-2Me-2,4-dppy)(2)Ir(tmd) and (3,5-2Me-dppy)(2)Ir(tmd) were synthesized with 2,4-diphenylpyridine of different methyl substituent positions as the main ligand and 2,2,6,6-tetramethylheptanedione as the auxiliary ligands. Their composition and spatial structure were characterized by elemental analysis, nuclear magnetic resonance (H-1 NMR and C-13 NMR) and single-crystal X-ray diffraction. Bothcomplexes show slightly distorted octahedral configuration with space groups of C 12 / C 1 and P-1, with monoclinic and triclinic crystal systems, respectively. The thermal stability was tested by TG curves, the two complexes have good thermal stability with thermal decomposition temperatures of 307 degrees C and 318 degrees C respectively. UV-Vis spectra and photoluminescence spectra studied the photophysical properties of the complexes. The emission wavelengths of the two complexes in solution were 545 and 572 nm, respectively. The quantum yields in solution were 70% and 92%, respectively. The effect of substituent position on the photophysical properties of iridium phosphorescent complexes was further discussed. It was found that the position of the methyl group had a significant effect on the luminescence color and emission wavelength of 2,4-diphenylpyridine iridium phosphorescent complexes. Compared with the iridium phosphorescent complex obtained when the methyl group is at the 2 and 4 positions, the emission wavelength of the iridium complex obtained when the methyl group is at the 3 and 5 positions has a significant redshift, which is pure yellow light emission. It is a potential yellow light material expected to be applied in OLED lighting.

Both polycyclic pyrimidin-4-one synthesis and the dehydrogenative coupling of malonates often require a redox agent, an elevated temperature, large amounts of transition-metal salts, and/or highly acidic/basic conditions, and the promising photoelectrocatalysis suffers from limited reaction patterns. We present herein a new photoelectrocatalytic mode and an electrolysis-photocatalysis-Bronsted base hybrid system for the synthesis of polycyclic pyrimidin-4-ones through dehydrogenative carbocyclization of unactivated alkenes with simple malonates under very mild and external-oxidant-free conditions. The reaction exhibits a good functional-group tolerance and is amenable for a gram-scale synthesis, and the sunlight could serve as the light source. Mechanistic studies suggest that the synergistic effect of light and electricity originates from the fast anchoring of an active electrochemical intermediate by the oxidative quenching photocatalytic cycle of Ir(ppy)3. A new photoelectrocatalytic mode permits the synthesis of polycyclic pyrimidin-4-ones through dehydrogenative cyclization of malonates with unactivated alkenes.

To study the effect of substituents on iridium phosphorescent complexes, fluorine, methoxy, or trifluoromethyl were introduced into positions 2 and 4 of phenyl at the same time to obtain 2,4.disubstituted phenyl-4-methylquinoline (2,4-2R-mpq). Three new iridium phosphorescent complexes (2,4-2R-mpq)(2)Ir(tmd) (R=F (1), MeO (2), CF3 (3)) were synthesized by using 2,2,6,6-tetramethylheptanedione (tmd) as the auxiliary ligand, and 2,4-2R-mpq with the electron-withdrawing group as the main ligands. The compositions and chemical structures of the complexes were characterized by elemental analysis, NMR spectroscopy, and single-crystal X-ray diffraction. The three iridium complexes belong to the triclinic system with the P (1) over bar space group. The photophysical properties of the complexes were studied by UV-Vis absorption spectroscopy, photoluminescence spectroscopy, and theory calculation. The results indicate that complexes 1, 2, and 3 with the photoluminescence quantum yields of 96%, 80%, and 80% exhibited maximum emission peaks at 570, 582, and 604 nm, respectively. When F and MeO are introduced into the 2 and 4 positions of phenyl on the main ligand, the electron cloud of complexes 1 and 2 are aggregated, while the CF3 is introduced, and the electron cloud of the complex is dispersed. Compared with complex 3, the emission wave. lengths of complexes 1 and 2 had a significant blue shift. Different from traditional cognition, the methoxyl group represents an electron-withdrawing group. CCDC: 2217725, 1; 2217726, 2; 2217727, 3.

以 1-苯基异喹啉(piq)为主配体,以 3-甲基-2-吡啶甲酸(mecid)为辅助配体合成了一种铱(Ⅲ)配合物 Ir(piq)2(mecid).采用元素分析、红外光谱、核磁共振谱分析和单晶 X 射线衍射对其化学组成和结构进行了表征.采用热失重(TGA)曲线分析了其热稳定性质,热分解温度为 325℃.采用紫外-可见光谱和光致发光光谱对其光物理性质进行了分析.结果表明,化学组成为C37H26IrN3O2,属于三斜晶系,P1/n 空间群.晶胞参数为 a=8.3130(4)nm,b=11.4866(5)nm,c=15.3737(7)nm,α=75.726(2)°,β=83.005(2)°,γ=88.785(2)°,V=1.4120(11)nm3,Z=2.光物理性质显示最大发射波长为 618 nm,为红色发射的铱磷光配合物.

以5-(4-氟苯基)-1,3-二甲基-1H-1,2,4-三唑(fdpt)为环金属主配体,4,4,4-三氟-1-(吡啶-3-基)-1,3-丁二酮(trifbutd)为辅助配体合成了一种铱(Ⅲ)配合物Ir(fdpt)2(trifbutd).采用元素分析、红外光谱、核磁共振谱分析和单晶X衍射对其化学组成及晶体结构进行了表征.采用紫外-可见光谱和光致发光荧光光谱对其光物理性质进行了分析.结果表明,该配合物化学组成为C29 H23 F5 IrN7 O2,属于单斜晶系,P21/n空间群.晶胞参数为a=1.17369(10)nm,b=1.68602(14)nm,c=1.42919(12)nm,β=90.925(3)°,V=2.8278(4)nm3,Z=4.光物理性质显示最大发射波长为620 nm,为红色发射.

A visible light-induced perfluoroalkylative cyclization of 3-aza-1,5-dienes leading to pentasubstituted 1,3-dihydropyrrole-2-ones is presented. The reaction is regiospecific, for the radical adds across the acrylamido moiety, whereas the enaminic double bond functions as a built-in radical trap. It could be carried out on a 2-gram scale, and the sunlight is a usable light source. Other virtues of the protocol include a short reaction time, a low catalyst loading, mild conditions and a broad substrate scope.