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1.
Artigo em Inglês | MEDLINE | ID: mdl-38683233

RESUMO

Nitro groups have been demonstrated to play a decisive role in the development of the most powerful known energetic materials. Two trinitromethyl-substituted 1H-1,2,4-triazole bridging nitropyrazoles were first synthesized by straightforward routes and were characterized by chemical (MS, NMR, IR spectroscopy, and single-crystal X-ray diffraction) and experimental analysis (sensitivity toward friction, impact, and differential scanning calorimetry-thermogravimetric analysis test). Their detonation properties (detonation pressure, detonation velocity, etc.) were predicted by the EXPLO5 package based on the crystal density and calculated heat of formation with Gaussian 09. These new trinitromethyl triazoles were found to show suitable sensitivities, high density, and highly positive heat of formation. The combination of exceedingly high performances superior to those of HMX (1,3,5,7-tetranitrotetraazacyclooctane), and its straightforward preparation highlights compound 8 as a promising high-energy density material (HEDM). This work supports the effectivity of utterly manipulable nitration and provides a generalizable design synthesis strategy for developing new HEDMs.

2.
Eur J Clin Pharmacol ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483544

RESUMO

BACKGROUND AND OBJECTIVES: Despite being clinically utilized for the treatment of infections, the limited therapeutic range of polymyxin B (PMB), along with considerable interpatient variability in its pharmacokinetics and frequent occurrence of acute kidney injury, has significantly hindered its widespread utilization. Recent research on the population pharmacokinetics of PMB has provided valuable insights. This study aims to review relevant literature to establish a theoretical foundation for individualized clinical management. METHODS: Follow PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, Pop-PK studies of PMB were searched in PubMed and EMBASE database systems from the inception of the database until March 2023. RESULT: To date, a total of 22 population-based studies have been conducted, encompassing 756 subjects across six different countries. The recruited population in these studies consisted of critically infected individuals with multidrug-resistant bacteria, patients with varying renal functions, those with cystic fibrosis, kidney or lung transplant recipients, patients undergoing extracorporeal membrane oxygenation (ECMO) or continuous renal replacement therapy (CRRT), as well as individuals with obesity or pediatric populations. Among these studies, seven employed a one-compartmental model, with the range of typical clearance (CL) and volume (Vc) being 1.18-2.5L /h and 12.09-47.2 L, respectively. Fifteen studies employed a two-compartmental model, with the ranges of the clearance (CL) and volume of the central compartment (Vc), the volume of the peripheral compartment (Vp), and the intercompartment clearance (Q) were 1.27-8.65 L/h, 5.47-38.6 L, 4.52-174.69 L, and 1.34-24.3 L/h, respectively. Primary covariates identified in these studies included creatinine clearance and body weight, while other covariates considered were CRRT, albumin, age, and SOFA scores. Internal evaluation was conducted in 19 studies, with only one study being externally validated using an independent external dataset. CONCLUSION: We conclude that small sample sizes, lack of multicentre collaboration, and patient homogeneity are the primary reasons for the discrepancies in the results of the current studies. In addition, most of the studies limited in the internal evaluation, which confined the implementation of model-informed precision dosing strategies.

3.
Dalton Trans ; 53(4): 1430-1433, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38180128

RESUMO

The development of energetic materials is still facing challenges due to the inherent contradiction between energy and sensitivity. Two new nitrogen-rich energetic salts of 3,4,5-1H-trinitropyrazole (HTNP) were synthesized. They are fully characterized by X-ray diffraction, NMR, MS and IR spectroscopy. The DSC and BAM tests were carried out as well. These TNP salts show high thermostability and high positive heat of formation. Their detonation performances were calculated by the EXPLO5 program. Most noteworthy is that DATr salt exhibits superior sensitivity and detonation performance comparable to secondary explosive RDX, making it promising for use as a new-generation green energetic material.

4.
Chem Commun (Camb) ; 60(12): 1595-1598, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38226668

RESUMO

Photoactive main-group complexes have been relatively underexplored in photocatalytic applications. Herein, we report a family of indium(III) complexes (In-1-In-4) containing pyridylpyrrolide ligands with different amounts of methyl groups, which all exhibit intense visible-light absorption as well as blue-green emission with nanosecond emission lifetimes and emission quantum yields of 6.7-12.5%. Electrochemical studies and quantum chemical calculations indicate that their (photo-)redox processes involve only ligand-centered events, which efficiently mediate photocatalytic dehalogenation and olefin reduction.

5.
Naunyn Schmiedebergs Arch Pharmacol ; 397(4): 2257-2267, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-37812240

RESUMO

Ursolic acid (UA), a pentacyclic triterpenoid, exhibits various pharmacological actions, such as anti-inflammation, anti-tumor, anti-diabetes, heart protection, and liver protection. However, the role of nuclear factor E2-related factor 2 (NRF2)-mediated regulation of uridine diphosphate glucuronosyltransferase (UGT2B7) and bile salt export pump (BSEP)/multidrug resistance-associated protein 2 (MRP2) in UA against cholestatic liver injury has not been cleared. The purpose of this study is to explore the effect of UA on cholestatic liver injury and its potential mechanism. The results of the liver pathology sections and blood biochemical indices demonstrated that UA significantly attenuated the cholestatic liver injury induced by alpha-naphthylisothiocyanate (ANIT) in a dose-dependent manner. The mRNA and protein levels of UGT2B7 and BSEP/MRP2 were remarkably increased in the liver of ANIT rats and HepG2 cells pretreated with UA, but this activation was suppressed with NRF2 silenced. In conclusion, our findings demonstrate that UA prevents cholestasis, which may be associated with NRF2-mediated regulation of UGT2B7, BSEP/MRP2.


Assuntos
Colestase , Proteína 2 Associada à Farmacorresistência Múltipla , Ratos , Animais , Ácido Ursólico , Fator 2 Relacionado a NF-E2/metabolismo , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Colestase/tratamento farmacológico , Fígado
6.
Inorg Chem ; 62(45): 18375-18383, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37910633

RESUMO

A series of novel Cp*Ir complexes with nitrogen-rich N̂N bidentate ligands were developed for the catalytic dehydrogenation of formic acid in water under base-free conditions. These complexes were synthesized by using pyridyl 1,2,4-triazole, methylated species, or pyridyl 1,2,3-triazole as a N-site regulation ligand and were fully characterized. Complex 1-H2O bearing 1,2,4-triazole achieved a high turnover frequency of 14192 h-1 at 90 °C in 4 M FA aqueous solution. The terminal and bridged Ir-H intermediates of 1-H2O were successfully detected by 1H NMR and mass spectrometry measurements. Kinetic isotope effect experiments and density functional theory (DFT) calculations were performed; then a plausible mechanism was proposed involving the ß-hydride elimination and formation of H2. Water-assisted H2 release was proven to be the rate-determining step of the reaction. The distribution of Mulliken charges on N atoms of triazole ligand internally revealed that the ortho site N2 of 1-H2O with a higher electron density was conducive to efficient proton transfer. Additionally, the advantage of water-assisted short-range bridge of 1,2,4-triazole moieties led to a higher catalytic activity of 1-H2O. This study demonstrated the effectiveness of nitrogen-rich ligands on FA dehydrogenation and revealed a good strategy for N site regulation in the development of new homogeneous catalysts.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37820472

RESUMO

Tamsulosin, the first highly selective α1-adrenoceptor antagonist, is widely used for urination disorders caused by benign prostatic hyperplasia (BPH). The pharmacokinetics and safety of 0.2 mg tamsulosin hydrochloride sustained-release capsules were evaluated in 60 healthy Chinese male subjects under fasting and fed conditions in this study. A simple, sensitive, and robust liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of tamsulosin in human plasma, which has been applied to pharmacokinetic study. The analyte and internal standard (tamsulosin-d5) were extracted by protein precipitation, and separated on a ZORBAX Eclipse XDB-C18 column (4.6 × 50 mm,1.8 µm; Agilent Tech) using a gradient elution with mobile phases methanol and 5 mM ammonium acetate. The linear range was 0.05-15.0 ng/mL. It showed good selectivity in normal, hyperlipidemic, and hemolyzed blank matrices. The CV (%) of intra-batch precision was <4.4% and the RE (%) of accuracy was in the range of -5.0%-6.7%; the CV (%) of inter-batch precision was <-5.8% and the RE (%) of accuracy was in the range of 1.2%-4.0%. The mean extraction recovery for the analyte was 102.1 ± 3.75% and for the IS was 102.2 ± 2.00%. Two formulations were considered bioequivalent under fasting and fed conditions, and the 90% confidence intervals for the geometric mean test/reference ratios were within the predetermined range of 80%-125%. A single oral dose of 0.2 mg tamsulosin hydrochloride sustained-release capsule was well-tolerated throughout the clinical trial, and no > Grade 1 adverse events (AEs) and serious AEs occurred during the trial.


Assuntos
População do Leste Asiático , Tansulosina , Humanos , Masculino , Cápsulas , Cromatografia Líquida , Preparações de Ação Retardada , Reprodutibilidade dos Testes , Tansulosina/farmacocinética , Espectrometria de Massas em Tandem
8.
Chem Sci ; 14(37): 10212-10218, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37772117

RESUMO

The accurate identification of catalytic sites in heterogeneous catalysts poses a significant challenge due to the intricate nature of controlling interfacial chemistry at the molecular level. In this study, we introduce a novel strategy to address this issue by utilizing a thiacalix[4]arene (TC4A)-protected Ti-oxo core as a template for loading Ag1+ ions, leading to the successful synthesis of a unique Ag/Ti bimetallic nanocluster denoted as Ti8Ag8. This nanocluster exhibits multiple surface-exposed Ag sites and possesses a distinctive "core-shell" structure, consisting of a {Ti4@Ag8(TC4A)4} core housing a {Ti2O2@Ag4(TC4A)2} motif and two {Ti@Ag2(TC4A)} motifs. To enable a comprehensive analysis, we also prepared a Ti2Ag4 cluster with the same {Ti2O2@Ag4(TC4A)2} structure found within Ti8Ag8. The structural disparities between Ti8Ag8 and Ti2Ag4 provide an excellent platform for a comparison of catalytic activity at different Ag sites. Remarkably, Ti8Ag8 exhibits exceptional performance in the electroreduction of CO2 (eCO2RR), showcasing a CO faradaic efficiency (FECO) of 92.33% at -0.9 V vs. RHE, surpassing the FECO of Ti2Ag4 (69.87% at -0.9 V vs. RHE) by a significant margin. Through density functional theory (DFT) calculations, we unveil the catalytic mechanism and further discover that Ag active sites located at {Ti@Ag2(TC4A)} possess a higher εd value compared to those at {Ti2O2@Ag4(TC4A)2}, enhancing the stabilization of the *COOH intermediate during the eCO2RR. This study provides valuable insights into the accurate identification of catalytic sites in bimetallic nanoclusters and opens up promising avenues for efficient CO2 reduction catalyst design.

9.
Inorg Chem ; 62(35): 14377-14384, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37620296

RESUMO

Nanocluster catalysts face a significant challenge in striking the right balance between stability and catalytic activity. Here, we present a thiacalix[4]arene-protected 6-electron [Ag30(TC4A)4(iPrS)8] nanocluster that demonstrates both high stability and catalytic activity. The Ag30 nanocluster features a metallic core, Ag104+, consisting of two Ag3 triangles and one Ag4 square, shielded by four {Ag5@(TC4A)4} staple motifs. Based on DFT calculations, the Ag104+ metallic kernel can be viewed as a trimer comprising 2-electron superatomic units, exhibiting a valence electron structure similar to that of the Be3 molecule. Notably, this is the first crystallographic evidence of the trimerization of 2-electron superatomic units. Ag30 can reduce CO2 into CO with a Faraday efficiency of 93.4% at -0.9 V versus RHE along with excellent long-term stability. Its catalytic activity is far superior to that of the chain-like AgI polymer ∞1{[H2Ag5(TC4A)(iPrS)3]} (∞1Agn), with the composition similar to Ag30. DFT calculations elucidated the catalytic mechanism to clarify the contrasting catalytic performances of the Ag30 and ∞1Agn polymers and disclosed that the intrinsically higher activity of Ag30 may be due to the greater stability of the dual adsorption mode of the *COOH intermediate on the metallic core.

10.
Inorg Chem ; 62(28): 11225-11232, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37401905

RESUMO

The regulation of ancillary ligands is critical to improve catalysis of Cp*Ir complexes for CO2 hydrogenation. Herein, a series of Cp*Ir complexes with N^N or N^O ancillary ligands were designed and synthesized. These N^N and N^O donors were derived from the pyridylpyrrole ligand. The solid-state structures of Cp*Ir complexes featured a pendant pyridyl group in 1-Cl and 1-SO4 and a pyridyloxy group in 2-Cl, 3-Cl, 2-SO4, and 3-SO4. These complexes were employed as catalysts for CO2 hydrogenation to formate in the presence of alkali under a pressure range of 0.1-8 MPa and temperature range of 25-120 °C. The catalytic activity of 2-SO4 with a pyridyloxy pendant group dramatically outperformed that of 1-SO4 and 3-SO4. The TOF of conversion of CO2 into formate reached 263 h-1 at 25 °C under a total pressure of 8 MPa (CO2/H2 = 1:1). The experiments and density functional theory calculations revealed that a pendant base in metal complexes plays a key role in the rate-determining heterolytic H2 splitting and enhancing the proton transfer by forming a hydrogen bonding bridge thereby improving the catalytic activity.

11.
Dalton Trans ; 52(17): 5438-5442, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37083046

RESUMO

Accurate manipulation of ligands at specific sites in robust clusters is attractive but difficult, especially for those ligands that coordinate in intricate binding patterns. By linking the shuttlecock-like {Cu4(µ4-Cl)TC4A} motif and the phenylphosphate (PhPO32-) ligand, we elaborately design and synthesize two Cu(II)-thiacalix[4]arene metallamacrocycles (MMCs), namely Cu12L3 and Cu16L4, which have regular triangular and quadrilateral topologies, respectively. While keeping the core intact, the Cl- and PhPO32- in those two MMCs, which coordinated in a µ4-bridging fashion, can be accurately substituted with salicylate ligands. Theoretical calculations have been carried out to reveal the effect of ligand tailoring on the electronic structure of clusters. Structural regulation can affect the catalytic activity of these clusters, which has been verified by using the clusters as catalysts for selective sulfide oxidation.

12.
Inorg Chem ; 62(15): 6047-6054, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37017204

RESUMO

This study used the tert-butylcalix[6]arene (TBC[6]) as the ligand and successfully synthesized six TBC[6]-stabilized titanium-oxo clusters (TOCs) by the one-step solvothermal reaction. These six compounds were [Ti4O2(TBC[6])2] (Ti4), {Ti2(TBC[6])(EtO)2(SaH2)2} (Ti2-SA, H2Sa = squaric acid), {Ti2(TBC[6])2(EtO)2(Oa)} (Ti2-OA, H2Oa = oxalic acid), [H2Ti4(TBC[6])(BA)2(EtO)10] (Ti4-BA, HBA = benzoic acid), [Ti6O2(TBC[6])(BA)4(OiPr)10] (Ti6-BA), and [Ti8(TBC[6])2(Sal)4(EtO)16] (Ti8-Sal, H2Sal = salicylic acid). These clusters contain one or two TBC[6] ligands, with the biconical or monoconical configuration, greatly increasing the variety of TOCs it could support. The introduction of auxiliary carboxylic ligands can further stimulate the growth of structures, with the cluster core gradually increased from {Ti-TBC[6]-Ti} to {Ti2-TBC[6]-Ti2}, to {Ti3-TBC[6]-Ti3}, and finally to {Ti3-TBC[6]-Ti2-TBC[6]-Ti3} with 3.1 nm length. Structural regulation may affect their solution stability, absorption spectra, and photocurrent response. The study of catalytic activities shows that these clusters can be used as recyclable heterogeneous photocatalysts for the oxidation of sulfide to sulfoxide. The catalytic efficiency of the TBC[6]-Tix system is closely related to the cluster structure, and the exposure of the Ti site on the catalyst surface can significantly enhance the catalytic activity of the clusters.

13.
Inorg Chem ; 62(7): 3186-3194, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36757804

RESUMO

Heat-resistant explosives play an irreplaceable role in specialized applications. Two energetic metal-organic frameworks (EMOFs), potassium 4,4'-oxybis[3,3'-(5-tetrazol)]furazan and potassium (1,2,4-triazol-3-yl)tetrazole, featuring a three-dimensional metal-organic framework structure, were first synthesized and characterized by chemical (1H NMR, 13C NMR, MS, IR spectroscopy, and single-crystal XRD) and physicochemical analyses (sensitivity toward friction, impact, electrostatic, and DSC-TGA test). The new 3D EMOFs were found to show high thermostability, highly positive heat of formation, and suitable sensitivities. The Hirshfeld surface was further analyzed in order to explore the effect on sensitivities. Their detonation properties (detonation velocity, detonation pressure, etc.) were calculated by the EXPLO5 program. K2NTT exhibits extremely high decomposition temperatures of up to 361 °C; meanwhile, its detonation performance is comparable to that of TATB and other energetic potassium salts, which makes it a promising heat-resistant explosive.

14.
J Am Chem Soc ; 145(1): 676-688, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36538810

RESUMO

Exploiting noble-metal-free systems for high-performance photocatalytic CO2 reduction still presents a key challenge, partially due to the long-standing difficulties in developing potent and durable earth-abundant photosensitizers. Therefore, based on the very cheap aluminum metal, we have deployed a systematic series of homoleptic Al(III) photosensitizers featuring 2-pyridylpyrrolide ligands for CO2 photoreduction. The combined studies of steady-state and time-resolved spectroscopy as well as quantum chemical calculations demonstrate that in anerobic CH3CN solutions at room temperature, visible-light excitation of the Al(III) photosensitizers leads to an efficient population of singlet excited states with nanosecond-scale lifetimes and notable emission quantum yields (10-40%). The results of transient absorption spectroscopy further identified the presence of emissive singlet and unexpectedly nonemissive triplet excited states. More importantly, the introduction of methyl groups at the pyrrolide rings can greatly improve the visible-light absorption, reducing power, and durability of the Al(III) photosensitizers. With triethanolamine, BIH (1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole), and an Fe(II)-quaterpyridine catalyst, the most methylated Al(III) photosensitizer achieves an apparent quantum efficiency of 2.8% at 450 nm for selective (>99%) CO2-to-CO conversion, which is nearly 28 times that of the unmethylated one (0.1%) under identical conditions. The optimal system realizes a maximum turnover number of 10250 and higher robustness than the systems with Ru(II) and Cu(I) benchmark photosensitizers. Quenching experiments using fluorescence spectroscopy elucidate that the photoinduced electron transfer in the Al(III)-sensitized system follows a reductive quenching pathway. The remarkable tunability and cost efficiency of these Al(III) photosensitizers should allow them as promising components in noble-metal-free systems for solar fuel conversion.

15.
Chem Commun (Camb) ; 58(64): 9034-9037, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35876039

RESUMO

High-valence Ti(IV)-based metallocalixarene coordination cages that are linked by oriented ancillary ligands are unknown so far. Herein, the first family of tunable calixarene-based coordination cages of Ti(IV) with a framework formula [Ti12(OiPr)12(TBC[4])6L6] have been assembled from six {Ti2(OiPr)2(TBC[4])}2+ nodes and six pyridinedicarboxylic ligands. Furthermore, the {Ti12L6} cage showed strong photocatalytic H2 evolution activity, and DFT studies were performed to explore its electronic structure.

16.
Inorg Chem ; 61(26): 10151-10158, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35748673

RESUMO

Incorporating heterometal into titanium-oxygen clusters (TOCs) is an effective way to improve its catalytic activity. Herein, we synthesize three novel heterometallic TOCs with the formula of [Ti6Cu2O7(Dmg)2(OAc)4(iPrO)6][H2Ti6Cu2O7(Dmg)2(OAc)4(iPrO)8] ({Ti6Cu2}), [Ti8Cu2O9(Dmg)2(OAc)2(iPrO)12] ({Ti8Cu2}), and [Ti10Co2O6(Dmg)2(Pdc)4(iPrO)18Cl3] ({Ti10Co2}, DmgH2 = dimethylglyoxime; PdcH2 = pyridine-2,3-dicarboxylic acid) using dimethylglyoxime and different carboxylates as the synergistic ligands. By depositing the clusters {Ti6Cu2} and {Ti10Co2} on carbon cloth as electrodes, we investigated the electrocatalytic performance of TOCs for full water splitting for the first time. To reach a 10 mA cm-2 current density in an alkaline solution, the {Ti10Co2}@CC electrode needs an overpotential as low as 120 and 400 mV for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively. In addition, full water-splitting equipment with {Ti10Co2}@CC as a cathode and an anode need only 1.67 V to deliver a current density of 10 mA cm-2. Our work confirmed the potential of noble metal-free TOCs as bifunctional cluster-based electrocatalysts for water splitting, and their activities can be tuned by doping with different metal ions.

17.
Chem Commun (Camb) ; 58(40): 6028-6031, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35502757

RESUMO

Polyhedral metallocalixarene nanocage clusters based on pure Ti(IV) ions are to our knowledge unknown hitherto. Herein we report the first Ti(IV)-based metallocalixarene nanocage cluster by assembling a [Ti13O14] cage with six t-butylcalix[4]arene molecules. Notably, the cluster exhibits extraordinary stability in high-concentration acid/alkali solutions and can act as a stable photocatalyst to catalyze the oxidation of ammonia to imines.

18.
Inorg Chem ; 61(6): 2903-2910, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35113567

RESUMO

Here, we systematically studied the self-assembly behavior of chiral polyoxytitanium clusters for the first time. Through the cooperative assembly of ferrocenecarboxylic acid and ketoxime ligands, we successfully incorporated the planar chirality of ferrocene (Fc) into the layered {Ti5} building blocks. The resulting {Ti5Fc} clusters can be used as structural units to assemble into large ordered structures in various ways; either a pair of {Ti5Fc} enantiomers are bridged by organic adhesive to form sandwich structures or two homochiral {Ti5Fc} units participate in the assembly to form the large clusters. Depending on the assembly modes, the chirality of {Ti5Fc} can be transferred to large nanoclusters or disappear to form mesostructures. The difference of the assembly modes between the {Ti5Fc} units can also tune the photoelectric activity of the resulting clusters, which has been verified by using {Ti10Fc-6/7} as catalysts for photocatalytic selective sulfide oxidation. This work not only is an important breakthrough in the study of the self-assembly of chiral nanoclusters but also provides an important reference for understanding of chiral transfer on the nanoscale.

19.
Inorg Chem ; 61(2): 923-930, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34968030

RESUMO

Cooperative assembly of the neutral cluster {Ti8O5(OEt)18L2} (L = pyrazine-2,3-dicarboxylic acid) with different metal units of Mn(NO3)2, CuCl2, Zn(OEt)2, Cd(NO3)2, Ce(NO3)3, Lu(NO3)3, and Lu(NO3)2(OEt), or the [Cu2I2] cluster, generates a family of titanium-oxygen cluster (TOC)-based coordination polymers. These one-dimensional (1D) linear structures contain the same {Ti8L2} cluster but with variable bridging metal units. The regulation of the heterometal not only affects the chain geometries of the {MTi8} but also affects the way the 1D chains are stacked in the crystal lattice. Investigation of the catalytic activities toward alcohol oxidation demonstrated the synergetic effect of combining the metal site and the photosensitive {Ti8L2} cluster in the tailored structure. Under light illumination, the {MTi8} with dual catalytic sites shows greatly enhanced catalytic activity in the selective oxidation of alcohols to aldehydes. Because the compositions and structures of {MTi8} are highly tunable, this work spotlights the potential of utilizing such metal-bridged multidimensional Ti-oxo materials for cooperative photoredox catalysis for organic transformation.

20.
Inorg Chem ; 60(24): 19263-19269, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34817992

RESUMO

Incorporating heterometal and chromogenic groups into the titanium oxo cluster (TOC) nanomaterials is one of the effective strategies for the development of new high-performance photoelectrically active materials. In this Article, we report the structures and photoelectrochemical (PEC) performances of a family of TOCs, including pure [Ti12O8(OEt)16L8] ({Me-Ti12}) and six Cd-doped clusters formulated as [H4Cd2Ti10O8(OEt)16(L)8(H2O)2] ({Cd2Ti10}; L = salicylic acid and their derivatives). The six Cd-doped clusters are isostructural, containing the same {Cd2Ti10O8} core, but are protected by salicylic ligands modified with different functional groups. The compositions, structures, and solution stability of these clusters have been studied in detail by single-crystal X-ray diffraction and electrospray ionization mass spectrometry measurements. The embedding of heterometallic Cd(II) and chemical modification of organic protective shells can effectively regulate the PEC water oxidation activity of those clusters, with {F-Cd2Ti10} having the highest turnover number of 518.55 and the highest turnover frequency of 172.85 h-1. Our work highlights the potential of using TOCs that do not contain noble metals as water oxidation catalysts, and their catalytic activity can be regulated by structural modification.

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