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1.
Inorg Chem ; 63(36): 16610-16621, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39193933

ABSTRACT

A series of structurally similar trinuclear macrocyclic copper(I) and silver(I) pyrazolate complexes bearing various short-bite diphosphine R2PCH(R')PR2 ligands are reported. Upon diphosphine coordination, the planar geometry of the initial complexes undergoes bending along the line between two metal atoms coordinated to the phosphorus moieties. The complexes based on dcpm ligands (R = cyclohexyl, R' = H, Ph) do not exhibit dynamic behavior in solution at room temperature on the 31P NMR time scale as it was previously observed for similar trinuclear copper complexes bearing the dppm (R = Ph, R' = H) scaffold. All copper(I) complexes exhibit thermally activated delayed fluorescence (TADF) behavior in the solid state. Importantly, the use of aliphatic substituents on the phosphorus atoms instead of aromatic ones leads to an almost double increase in the quantum efficiency (ΦPL) of photoluminescence by eliminating nonradiative decay from the 3LCPh states of the dppm aromatic rings. The higher donating ability of the substituents in the pyrazolate ligand (CF3 vs CH3) lowers the energy of the metal-centered excited state, allowing for a significant metal impact on the T1 state. Finally, the Ag(I) complex displays an emission efficiency of approximately 14%, being the highest among known trinuclear silver(I) pyrazolate homometallic derivatives.

2.
Nat Commun ; 15(1): 7261, 2024 Aug 23.
Article in English | MEDLINE | ID: mdl-39179587

ABSTRACT

Effectively regulating monomer and excimer emission in a singular supramolecular luminous platform is challenging due to high difficulty of precise control over its aggregation and dispersion behavior when subjected to external stimuli. Here, we show a metallo-cage (MTH) featuring a triple helical motif that displays a unique dual emission. It arises from both intramolecular monomer and intermolecular excimer, respectively. The distorted molecular conformation and the staggered stacking mode of MTH excimer are verified through single crystal X-ray diffraction analysis. These structural features facilitate the switch between monomer and excimer emission, which are induced by changes in concentration and temperature. Significantly, adjusting the equilibrium between these two states in MTH enables the production of vibrant white light emission in both solution and solid state. Moreover, when combined with a PMMA (polymethyl methacrylate) substrate, the resulting thin films can serve as straightforward fluorescence thermometer and thermally activated information encryption materials.

3.
Chem Sci ; 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39170716

ABSTRACT

The development of metal complexes for photosynthesis of hydrogen peroxide (H2O2) from pure water and oxygen using solar energy, especially in the absence of any additives (e.g., acid, co-catalysts, and sacrificial agents), is a worthwhile pursuit, yet still remains highly challenging. More importantly, the O2 evolution from the water oxidation reaction has been impeded by the classic bottleneck, the photon-flux-density problem of sunlight that could be attributed to rarefied solar radiation for a long time. Herein, we reported synthesis of boron dipyrromethene (BODIPY)-based cyclic trinuclear silver complexes (Ag-CTC), and they exhibited strong visible-light absorption ability, a suitable energy bandgap, excellent photochemical properties and efficient charge separation ability. The integration of BODIPY motifs as oxygen reduction reaction sites and silver ions as water oxidation reaction sites allows Ag-CTC to photosynthesize H2O2 either from pure water or from sea water in the absence of any additives with a high H2O2 production rate of 183.7 and 192.3 µM h-1, which is higher than that of other reported metal-based photocatalysts. The photocatalytic mechanism was systematically and ambiguously investigated by various experimental analyses and density functional theory (DFT) calculations. Our work represents an important breakthrough in developing a new Ag photocatalyst for the transformation of O2 into H2O2 and H2O into H2O2.

4.
J Am Chem Soc ; 146(28): 19271-19278, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-38950195

ABSTRACT

Developing efficient, low-cost, MOF catalysts for CO2 conversion at low CO2 concentrations under mild conditions is particularly interesting but remains highly challenging. Herein, we prepared an isostructural series of two-dimensional (2D) multivariate metal-organic frameworks (MTV-MOFs) containing copper- and/or silver-based cyclic trinuclear complexes (Cu-CTC and Ag-CTC). These MTV-MOFs can be used as efficient and reusable heterogeneous catalysts for the cyclization of propargylamine with CO2. The catalytic performance of these MTV-MOFs can be engineered by fine-tuning the Ag/Cu ratio in the framework. Interestingly, the induction of 10% Ag remarkably improved the catalytic efficiency with a turnover frequency (TOF) of 243 h-1, which is 20-fold higher than that of 100% Cu-based MOF (i.e., TOF = 10.8 h-1). More impressively, such a bimetallic MOF still exhibited high catalytic activity even for simulated flue gas with 10% CO2 concentration. Furthermore, the reaction mechanism has been examined through the employment of NMR monitoring experiments and DFT calculations.

5.
Angew Chem Int Ed Engl ; 63(36): e202408186, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-38895811

ABSTRACT

The development of novel metal-organic frameworks (MOFs) as efficient photocatalysts for hydrogen peroxide production from water and oxygen is particularly interesting, yet remains a challenge. Herein, we have prepared four cyclic trinuclear units (CTUs) based MOFs, exhibiting good light absorption ability and suitable band gaps for photosynthesis of H2O2. However, Cu-CTU-based MOFs are not able to photocatalyzed the formation of H2O2, while the alteration of metal nodes from Cu-CTU to Ag-CTU dramatically enhances the photocatalytic performance for H2O2 production and the production rates can reach as high as 17476 µmol g-1 h-1 with an apparent quantum yield of 4.72 %, at 420 nm, which is much higher than most reported MOFs. The photocatalytic mechanism is comprehensively studied by combining the isotope labeling experiments and DFT calculation. This study provides new insights into the preparation of MOF photocatalysts with high activity for H2O2 production through molecular engineering.

6.
MycoKeys ; 102: 83-105, 2024.
Article in English | MEDLINE | ID: mdl-38370857

ABSTRACT

During our investigation of saprophytic fungi in Guizhou and Hainan provinces, China, three hyphomycetes were collected from terrestrial and freshwater habitats. Based on morphological characteristics and phylogenetic analyses of combined ITS, LSU, tef1-α, and rpb2 sequence data, two new species are introduced: Distoseptisporahainanensis and D.lanceolatispora. Additionally, one known species, D.tectonae, previously unreported from Edgeworthiachrysantha, is newly reported. Detailed descriptions, illustrations, and a phylogenetic tree to show the two new species and the new host record of Distoseptispora are provided. In addition, a checklist of Distoseptispora species with their locations, lifestyles, habitats, and hosts is provided.

7.
Chemistry ; 30(26): e202400360, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38376356

ABSTRACT

Owing to well-defined structure as well as easy synthesis and modification, metal-organic frameworks (MOFs) have emerged as promising catalysts for tandem reactions. In this article, we aim to summarize the development of multifunctional MOFs, including mixed metal MOFs, MOFs that are synergistically catalyzed by metal nodes and organic linkers, MOFs loaded with metal nanoparticles, etc, as heterogenous catalysts for tandem reactions over the past five years. This concept briefly discusses on present challenges, future trends, and prospects of multifunctional MOFs catalysts in tandem reactions.

8.
Nat Commun ; 15(1): 194, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38172097

ABSTRACT

The properties of two-dimensional covalent organic frameworks (2D COFs), including porosity, catalytic activity as well as electronic and optical properties, are greatly affected by their interlayer stacking structures. However, the precise control of their interlayer stacking mode, especially in a reversible fashion, is a long-standing and challenging pursuit. Herein, we prepare three 2D copper-organic frameworks, namely JNM-n (n = 7, 8, and 9). Interestingly, the reversible interlayer sliding between eclipsed AA stacking (i.e., JNM-7-AA and JNM-8-AA) and staggered ABC stacking (i.e., JNM-7-ABC and JNM-8-ABC) can be achieved through environmental stimulation, which endows reversible encapsulation and release of lipase. Importantly, JNM-7-AA and JNM-8-AA exhibit a broader light absorption range, higher charge-separation efficiency, and higher photocatalytic activity for sensitizing O2 to 1O2 and O2•- than their ABC stacking isostructures. Consequently, JNM-8-AA deliver significantly enhanced photocatalytic activities for oxidative cross-coupling reactions compared to JNM-8-ABC and other reported homogeneous and heterogeneous catalysts.

9.
Small ; 20(13): e2306863, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37963848

ABSTRACT

The construction of stable copper nanoclusters (Cu-NCs) with near-infrared (NIR) emission that can be used for catalysis is highly desired, yet remains a challenge. Herein, an atomically precise bimetallic Cu/Pd NC with a molecular formula of Cu16Pd1L10(PPh3)2(Pz)6 (Pz = 3,5-(CF3)2Pyrazolate, L = 4-CH3OPhC≡C-), abbreviated as Cu16Pd1, is synthesized. Single-crystal X-ray crystallographic analysis of Cu16Pd1 reveals a Cu10Pd1 kernel with pseudo-gyroelongated square bipyramid confirmation surrounded by other 6 Cu(I) ions and protected ligands. Interestingly, it exhibits strong NIR emission with the highest photoluminescence quantum yield (PLQY) among all the Cu NCs/Cu alloys (λem > 800 nm) in the solid-state, and also displays NIR emission in solution. Experimental results and theoretical calculations suggest that the impressive NIR emission is attributed to abundant supramolecular interactions in the solid-state, including intramolecular metal-metal and intermolecular interactions. Of note, the bimetallic Cu16Pd1 can catalyze the reduction of 4-nitrophenol. This work provides a novel method for synthesizing Cu/Pd NCs and reminds that the less studied Cu/Pd NC can serve as outstanding luminescent material, which is seldom noticed in atomically precise nanoclusters.

10.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1022645

ABSTRACT

Objective To investigate the correlation between non-high density lipoprotein cholesterol(non-HDL-C),homocysteine(Hey)levels and cognitive impairment,prognosis in patients with thalamic infarction.Methods Eighty thalamic infarction patients admitted to Puyang People's Hospital from March 2017 to March 2021 were selected as the research sub-jects.According to Montreal cognitive assessment(MoCA)score,the patients were divided into cognitive impairment group(MoCA score<26,n=35)and cognitive normal group(MoCA score 26-30,n=45).Another 50 healthy individuals who un-derwent physical examinations during the same period were selected as the control group.The serum cholesterol(TC),high-density lipoprotein cholesterol(HDL-C),Hcy levels of all subjects were detected by fully automated biochemical analyzer,and the non-HDL-C levels were calculated.The correlations between non-HDL-C,Hey levels and MoCA scores were analyzed by Pearson correlation analysis,and the diagnostic efficacy of non-HDL-C,Hcy levels for cognitive impairment of patients with tha-lamic infarction was analyzed by receiver operating characteristic curve.According to the modified Rankin scale(mRS)score,the patients with thalamic infarction were divided into good prognosis group(mRS score ≤2,n=50)and poor prognosis group(mRS score 3-6,n=50).The independent risk factors for poor prognosis of patients with thalamic infarction was analyzed by multivariate logistic regression.Results The serum levels of non-HDL-C and Hcy of patients in the cognitive impairment group were significantly higher than those in the cognitive normal group and control group(P<0.05);there was no significant difference in the serum non-HDL-C,Hcy levels of subjects between the control group and the cognitive normal group(P>0.05).The non-HDL-C,Hcy levels were negatively correlated with MoCA scores in thalamic infarction patients(P<0.05).The area under the curve(AUC)of Hcy level in the diagnosis of cognitive impairment was 0.709,the sensitivity was 0.724 and the specificity was 0.630;the AUC of non-HDL-C level in the diagnosis of cognitive impairment was 0.738,the sensitivity was 0.701 and the specificity was 0.870;the AUC of Hey combined with non-HDL-C in the diagnosis of cognitive impairment was 0.769,the sensitivity was 0.758 and the specificity was 0.889.The diagnostic efficacy of Hey combined with non-HDL-C for cognitive impairment was superior to that of non-HDL-C or Hey alone.Atrial fibrillation,elevated levels of non-HDL-C,Hcy and NIHSS score were independent risk factors for poor prognosis of patients with thalamic infarction(P<0.05).Conclusion The levels of non-HDL-C and Hey are positively correlated with cognitive impairment in patients with thalamic infarction.The levels of non-HDL-C and Hey can be used to diagnose cognitive impairmnent in patients with thalamic infarction,and the combined detection has a better diagnostic effect.Atrial fibrillation,elevated levels of non-HDL-C,Hcy and NIHSS score are independent risk factors for poor prognosis in patients with thalamic infarction.

11.
Front Microbiol ; 14: 1253239, 2023.
Article in English | MEDLINE | ID: mdl-38116531

ABSTRACT

During the survey on freshwater hyphomycetes in Guangxi, Guizhou and Hainan Provinces, China, five fresh collections were encountered. Based on their morphology, these five isolates were identified as belonging to Hermatomyces, Kirschsteiniothelia, Paramonodictys, Pleopunctum and Sparticola. Multi-gene phylogenetic analyses were performed for each genus, which resulted in the identification of five new species, namely Hermatomyces hainanensis, Kirschsteiniothelia ramus, Paramonodictys globosa, Pleopunctum guizhouense, and Sparticola irregularis. Detailed descriptions and illustrations of the morphological characteristics of these new taxa were provided. This research enriches the biodiversity of freshwater dematiaceous hyphomycetes.

12.
Chem Asian J ; 18(23): e202300857, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37927167

ABSTRACT

The development of efficient, recyclable and low-cost heterogeneous catalysts for conversion of carbon dioxide (CO2 ) into epoxides is highly desired, yet remain a challenge. Herein, we have prepared three two-dimensional (2D) copper(I) cyclic trinuclear units (Cu(I)-CTUs) based covalent metal-organic frameworks (CMOFs), namely JNM-13, JNM-14, and JNM-15, via a one-pot reaction by combination of coordination and dynamic covalent chemistry. Among them, JNM-15 contained the highest density of copper catalytic sites, and exhibited the highest capacity for adsorption of CO2 . More interestingly, JNM-15 delivered the highest catalytic activity for cycloaddition of CO2 to epoxides with good yields (up to 99 %), good substrate compatibility (11 examples) and reusability (four catalytic cycles) under mild condition.

13.
J Am Chem Soc ; 145(41): 22720-22727, 2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37791919

ABSTRACT

Construction of gold-based metal-organic frameworks (Au-MOFs) would bring the merits of gold chemistry into MOFs. However, it still remains challenging because gold cations are easily reduced to metallic gold under solvothermal conditions. Herein, we present the first example of Au-MOFs prepared from the networking of cyclic trinuclear gold(I) complexes by formal transimination reaction in a rapid (<15 min) and scalable (up to 1 g) fashion under ambient condition. The Au-MOFs feature uniform porosity, high crystallinity, and superior chemical stability toward base (i.e., 20 M NaOH). With open Au(I) sites in the skeleton, the Au-MOFs as heterogeneous catalysts delivered good performance and substrate tolerance for the carboxylation reactions of alkynes with CO2. This work demonstrates a facile approach to reticularly synthesize Au-MOFs by combining the coordination and dynamic covalent chemistry.

14.
Angew Chem Int Ed Engl ; 62(50): e202315020, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-37884445

ABSTRACT

The development of energy-saving technology for the efficient separation of olefin and paraffin is highly important for the chemical industry. Herein, we report a self-assembled Fe4 L6 capsule containing a hydrophobic cavity, which can be used to encapsulate and separate propylene/propane. The successful encapsulation of propylene and propane by the Fe4 L6 cage in a water solution was documented by NMR spectroscopy. The binding constants K for the Fe4 L6 cage toward propylene and propane were determined to be (5.0±0.1)×103  M-1 and (2.1±0.7)×104  M-1 in D2 O at 25 °C, respectively. Experiments and theoretical studies revealed that the cage exhibited multiple weak interactions with propylene and propane. The polymer-grade propylene (>99.5 %) can be obtained from a mixture of propylene and propane by using the Fe4 L6 cage as a separation material in a U-shaped glass tube. This work provides a new strategy for the separation of olefin/paraffin.

15.
MycoKeys ; 99: 87-108, 2023.
Article in English | MEDLINE | ID: mdl-37614656

ABSTRACT

During an investigation of helicosporous fungi in China, a total of seven helicosporous hyphomycetes were obtained from decaying wood in the southern region of the country. Based on phylogenetic analyses using a combined LSU, ITS, tef1α, and rpb2 sequence matrix, in conjunction with morphological comparisons, these taxa were classified within Tubeufia (Tubeufiaceae, Tubeufiales) and were recognized as three new species, viz. Tubeufiaguttulata, T.hainanensis, and T.muriformis, as well as one new distribution record, viz. T.cocois. Evidence for these new taxa and the new record, descriptions, illustrations, notes, and phylogenetic evidence are provided for the newly collected helicosporous species.

16.
J Fungi (Basel) ; 9(7)2023 Jul 12.
Article in English | MEDLINE | ID: mdl-37504731

ABSTRACT

Three helicosporous hyphomycete collections representing two species were obtained from rotting wood found in freshwater and terrestrial habitats in the Guizhou and Guangxi Provinces, China. A new genus Pseudotubeufia (Tubeufiaceae, Tubeufiales), comprising Ps. hyalospora sp. nov. and Ps. laxispora sp. nov., was introduced with morphological characteristic and molecular data. In addition, the molecular evidence showed that Helicomyces sp. (G.M. 2020-09-19.1), H. roseus (CBS: 102.76), and the new genus Pseudotubeufia clustered together with high support based on a multi-gene (LSU, ITS, tef1α, and rpb2) phylogenetic analysis. Detailed descriptions, illustrations, and notes of the three new collections are provided.

17.
J Fungi (Basel) ; 9(7)2023 Jul 22.
Article in English | MEDLINE | ID: mdl-37504763

ABSTRACT

Helicosporous hyphomycetes is a group of filamentous fungi that shows promising application prospects in metabolizing bioactive natural compounds. During a study of helicosporous fungi in China, six new helicosporous taxa were collected and isolated from decaying wood in Guangxi Zhuang Autonomous Region, China. Morphological comparisons with multi-gene phylogenetic analyses revealed that these six taxa belong to Helicosporium (Tubeufiaceae, Tubeufiales), and they were recognized as three novel species and were named Helicosporium liuzhouense, H. multidentatum, and H. nanningense. Detailed descriptions and illustrations of the newly discovered taxa and comparisons with similar fungi are provided. In addition, a list and a key to accepted Helicosporium species are provided.

18.
Angew Chem Int Ed Engl ; 62(35): e202306497, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37259979

ABSTRACT

Owing to the wide and growing demand for primary alcohols, the development of efficient catalysts with high regioselectivity remains a worthwhile pursuit. However, according to Markovnikov's rule, it is a challenge to obtain primary alcohols with high yields and regioselectivity from terminal alkenes or alkynes. Herein, we report the synthesis of a photosensitizing two-dimensional (2D) metal-organic framework (MOF) from cyclic trinuclear copper(I) units (Cu-CTUs) and a boron dipyrro-methene (Bodipy) ligand. The MOF features broadband light absorption, excellent photoinduced charge separation efficiency, and photochemical properties. By integrating the copper-catalyzed hydroboration and photocatalyzed aerobic oxidation, it can catalyze terminal alkenes and alkynes to produce primary alcohols via a one-pot tandem reaction with excellent regioselectivity, good overall yields in two-step reactions (up to 85 %), broad substrate compatibility (32 examples) and good reusability under mild conditions.

19.
J Fungi (Basel) ; 9(5)2023 May 12.
Article in English | MEDLINE | ID: mdl-37233273

ABSTRACT

During the investigation of lignicolous freshwater fungi in the Tibetan Plateau habitat, fifteen collections were isolated from submerged decaying wood. Fungal characteristics are commonly found as punctiform or powdery colonies with dark pigmented and muriform conidia. Multigene phylogenetic analyses of combined ITS, LSU, SSU and TEF DNA sequences showed that they belong to three families in Pleosporales. Among them, Paramonodictys dispersa, Pleopunctum megalosporum, Pl. multicellularum and Pl. rotundatum are established as new species. Paradictyoarthrinium hydei, Pleopunctum ellipsoideum and Pl. pseudoellipsoideum are reported as new records on the freshwater habitats in Tibetan Plateau, China. The morphological descriptions and illustrations of the new collections are provided.

20.
Chem Asian J ; 18(13): e202300328, 2023 Jul 03.
Article in English | MEDLINE | ID: mdl-37194612

ABSTRACT

Covalent organic frameworks (COFs) as metal-free photocatalysts have attracted extensive interest. However, the organic transformations photocatalyzed by COFs under mild conditions remain a challenge. Herein, a boron-dipyrromethene (BODIPY) based 1D COF, namely JNM-12, was facilely constructed by Schiff-base condensation reaction. JNM-12 exhibited strong visible-light harvesting abilities and suitable photocatalysis energy potentials, enabling the activation of O2 to superoxide anions (O2 ⋅- ) and singlet oxygen (1 O2 ) under visible light irradiation. Benefiting from these properties, JNM-12 delivered excellent photocatalytic activity in the O2 ⋅- -mediated oxidative coupling of amines and 1 O2 -engaged aerobic oxidation of enamines. Our work paves a new way for synthesis of COFs as efficient, economical, and green photocatalysts for organic synthesis.

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