The reaction of the lithium aryl(silyl)amide Dipp(iPr3Si)NLi (Dipp=2,6‐iPr2C6H3) with one equivalent of SnCl2 in THF gave a novel stannylenoid Dipp(iPr3Si)NSnCl⋅LiCl(THF)2. Heating the solution of ...amidostannylenoid in toluene to 80 °C resulted in dimeric amido(chloro)stannylene Dipp(iPr3Si)NSnCl2, which can be converted to bis(amido)stannylene SnN(Dipp)(iPr3Si)2 and amido(imino)stannylene SnN(Dipp)(iPr3Si)IPrN (IPrN=bis(2,6‐diisopropylphenyl)imidazolin‐2‐imino). Treatment of bis(imino)stannylenoid IPrN2Sn(Cl)Li with N2O resulted in the dimeric complex IPrNSn(Cl)OLi2. All compounds were characterized by NMR, elementary analysis, and X‐ray structural determination.
A novel stannylenoid was isolated by using a bulky amido ligand. It can be converted to the dimeric chlorostannylene at 80 °C with the elimination of LiCl. Treatment of the amidostannylenoid with IPrNLi (IPrN=bis(2,6‐diisopropylphenyl)imidazolin‐2‐iminato) led to the formation of amido(imino)stannylene. In addition, the reaction of bis(imino)stannylenoid with N2O resulted in a dimeric Sn/O/Li complex.
The germanium iron carbonyl complex 3 was prepared by the reaction of dimeric chloro(imino)germylene IPrNGeCl2 (IPrN=bis(2,6‐diisopropylphenyl)imidazolin‐2‐iminato) with one equivalent of Collman's ...reagent (Na2Fe(CO)4) at room temperature. Similarly, the reaction of chloro(imino)stannylene IPrNSnCl2 with Na2Fe(CO)4 (1 equiv) resulted in the Fe(CO)4‐bridged bis(stannylene) complex 4. We observed reversible formation of bis(tetrylene) and tetrylene‐tetrylone character in complexes 3 vs. 5 and 4 vs. 6, which was supported by DFT calculations. Moreover, the Li/Sn/Fe trimetallic complex 12 has been isolated from the reaction of IPrNSnCl2 with cyclopentadienyl iron dicarbonyl anion. The computational analysis further rationalizes the reduction pathway from these chlorotetrylenes to the corresponding complexes.
The germanium and tin iron carbonyl complexes were prepared by the reaction of dimeric chloro(imino)tetrylenes IPrNECl2 (E=Ge, Sn; IPrN=bis(2,6‐diisopropylphenyl)imidazolin‐2‐iminato) with one equivalent of Na2Fe(CO)4 at room temperature. Besides, a Li/Sn/Fe trimetallic complex was isolated by the reaction of chloro(imino)stannylene with cyclopentadienyl iron dicarbonyl anion.
A rare three‐coordinate germanone IPrN2Ge=O (IPrN=bis(2,6‐diisopropylphenyl)imidazolin‐2‐imino) was successfully isolated. The germanone has a rather high thermal stability in arene solvent, and no ...detectable change was observed at 80 °C for at least one week. However, high thermal stability of IPrN2Ge=O does not prevent its reactivity toward small molecules. Structural analysis and initial reactivity studies revealed the highly polarized nature of the terminal Ge=O bond. Besides, the addition of phenylacetylene, as well as O‐atom transfer with 2,6‐dimethylphenyl isocyanide make it a mimic of nucleophilic transition‐metal oxides. Mechanism for O‐atom transfer reaction was investigated via DFT calculations, which revealed that the reaction proceeds via a 2+2 cycloaddition intermediate.
A rare three‐coordinate germanone: bis(imino)germanone IPrN2Ge=O (IPrN=bis(2,6‐diisopropylphenyl)imidazolin‐2‐imino) was successfully isolated. Initial reactivity studies combined with experimental and computational bonding analysis revealed highly polarized nature of the terminal Ge=O bond. Moreover, transition metal oxide‐like reactivity has been observed for the addition of phenylacetylene, as well as O‐atom transfer with 2,6‐dimethylphenyl isocyanide.
The massive amount of information brought about by the era of big data has enormous potential value. In-depth discussion and analysis of solving the information asymmetry between tax collection and ...taxpayers are keys. This paper provides an in-depth study and analysis of the fiscal and tax intelligent risk management strategies of listed companies in the big data environment. The tax risk management of listed companies is optimized. Tax authorities should follow the development trend of big data, apply big data thinking, comprehensively excavate and utilize tax-related information, and improve the tax risk management model. At the same time, they should make full use of information technology to solve the problem of information asymmetry between tax collection and taxpayers and improve the quality and efficiency of tax risk management. The work discusses the problems of the current tax collection and management model in terms of management thinking, information collection, data analysis, legal system, and talent technology, and analyses the challenges brought by big data technology to the tax collection and management model as well as tax source management and tax informatization.
Comprehensive Summary
The Haber‐Bosch process, which is used for ammonia (NH3) synthesis, requires vast amounts of energy, accounting for approximately 1%—2% of the world's annual energy consumption. ...Therefore, researchers in both industry and academia are interested in developing sustainable and environmentally friendly methods for synthesizing nitrogenous compounds at ambient conditions using renewable energy sources such as visible light. While several examples of thermal activation of dinitrogen molecules have been demonstrated using various transition metals and ligand frameworks, the use of light to weaken or split the strong N—N bond has been less explored. This article presents an overview of molecular complexes capable of dinitrogen photocleavage and provides mechanistic insights into the photoactivation process through experimental and theoretical studies. We believe this review will provide readers with an in‐depth understanding of the current state‐of‐the‐art and future research perspectives, particularly in the use of visible light for dinitrogen activation and transformation.
Developing green and sustainable strategies for the synthesis of nitrogenous compounds under ambient conditions, using renewable energy, such as visible light, is in high demand. To date, the use of light to induce weakening or splitting of the strong N—N bond has been less well explored. This review summarizes the progress of dinitrogen photoactivation mediated by molecular catalysts, and discusses the related mechanisms. We hope this review can provide readers with a better understanding of the state‐of‐the‐art and perspectives for future research in this field.
Vascular endothelial cells (VECs) that form the inner wall of blood vessels can be injured by high glucose-induced autophagy and apoptosis. Although the role of long noncoding RNA in regulating cell ...fate has received widespread attention, long noncoding RNAs (lncRNAs) that can both regulate autophagy and apoptosis need to be discovered. In this study, we identified that a small chemical molecule, 3-benzyl-5-(2-nitrophenoxy methyl)-dihydrofuran-2(3H)-one (3BDO), synthesized by us, could inhibit VEC autophagy and apoptosis induced by a high concentration of glucose. To find new lncRNAs that regulate autophagy and apoptosis in VECs, we performed lncRNA microarray analysis. We found and verified an upregulated lncRNA named CA7-4 that was induced by a high concentration of glucose could be downregulated by 3BDO most obviously among all of the detected lncRNAs. Meanwhile, we investigated the mechanism of CA7-4 in regulating VEC autophagy and apoptosis. The results showed that CA7-4 facilitated endothelial autophagy and apoptosis as a competing endogenous RNA (ceRNA) by decoying MIR877-3P and MIR5680. Further study elucidated that MIR877-3P could trigger the decrease of CTNNBIP1 (catenin beta interacting protein 1) by combining with its 3ʹ UTR and then upregulating CTNNB1 (catenin beta 1); MIR5680 inhibited the phosphorylation of AMP-activated protein kinase (AMPK) by targeting and decreasing DPP4 (dipeptidyl peptidase 4). Therefore, CA7-4, MIR877-3P and MIR5680 represent new signal pathways that regulate VEC autophagy and apoptosis under the high-glucose condition.
Abbreviations: 3BDO: 3-benzyl-5-(2-nitrophenoxy methyl)-dihydrofuran-2(3H)-one; 3ʹ UTR: 3ʹ untranslated region; AGO2: argonaute RISC catalytic component 2; AMPK: AMP-activated protein kinase/protein kinase AMP-activated; BAX/BCL2L4: BCL2 associated X, apoptosis regulator; BCL2: BCL2 apoptosis regulator; CASP3: caspase 3; ceRNA: competing endogenous RNA; CTNNB1: catenin beta 1; CTNNBIP1/ICAT: catenin beta interacting protein 1; DPP4: dipeptidyl peptidase 4; FGF2/FGF-2: fibroblast growth factor 2; HG: high concentration glucose (30 mM glucose); lncRNA: long noncoding RNA; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; miRNA: microRNA; MIR4778-3P: microRNA 4778-3p; MIR561-3P: microRNA 561-3p; MIR5680: microRNA 5680; MIR877-3P: microRNA 877-3p; MTOR: mechanistic target of rapamycin kinase; Mut: mutant; NC: negative control; NG: normal concentration glucose (5.5 mM glucose); PARP1: poly(ADP-ribose) polymerase 1; qPCR: quantitative real-time PCR; RNA-FISH: RNA-fluorescence in situ hybridization; ROS: reactive oxygen species; RT-PCR: reverse transcription polymerase chain reaction; siRNA: small interfering RNA; SQSTM1: sequestosome 1; TGFB2-OT1: TGFB2 overlapping transcript 1; TUNEL: terminal deoxynucleotidyl transferase dUTP nick end labeling; VECs: vascular endothelial cells; WT: wild type
The reaction of Cp*SnOTf (Cp*=C5Me5; OTf=O3SCF3) with one equivalent of IPrNLi (IPrN=bis(2,6‐diisopropylphenyl)imidazolin‐2‐iminato) resulted in the binuclear OTf‐bridged tin complex 1. Similarly, ...the BF4‐bridged bimetallic complex 2 was synthesized by the reaction of Cp*SnBF4 with IPrNLi (1 eq.). It was also possible to prepare 1 from 2 via an anion exchange reaction. The high‐yield conversion of 2 into the binuclear iodostannylene IPrNSnI2 3 was accomplished by treatment with LiI. The catalytic potential of 1 and 2 was demonstrated in the hydroboration of carbonyls.
In this paper, a novel compact operator is derived for the approximation of the Riesz derivative with order $\alpha\in(1,2.$ The compact operator is proved with fourth-order accuracy. Combining the ...compact operator in space discretization, a linearized difference scheme is proposed for a two-dimensional nonlinear space fractional Schrodinger equation. It is proved that the difference scheme is uniquely solvable, stable, and convergent with order $O(\tau arrow up +h pound sterling )$, where $\tau$ is the time step size, $h=\max\{h_1,h_2\}$, and $h_1,\,h_2$ are space grid sizes in the $x$ direction and the $y$ direction, respectively. Based on the linearized difference scheme, a compact alternating direction implicit scheme is presented and analyzed. Numerical results demonstrate that the compact operator does not bring in extra computational cost but improves the accuracy of the scheme greatly.
The research aims at providing a comparative study of the impersonal The research aims at providing a comparative study of the impersonal structure (e.g., NGL ^ VG ^ NG structure) by using data from ...Chinese, English, Hungarian, Burmese and Persian and construing the linguistic phenomenon from the cognitive perspective. A typological approach is used for the cross-linguistic study. Results show that when translating the impersonal structure from Chinese into other four languages, the structure can be best preserved in Hungarian while partially preserved in Burmese and Persian. However, the structure has to be completely changed into passive voice structure in English if we do not add any expletive subject to make the sentence complete. The author concludes that grammatical structure is closely related to speakers’ perception of the world, which might explain the similarities between languages within different families.
•The adsorbent is novel and can be practical.•Fast adsorption and high adsorption capacity for acid dyes were observed.•Our adsorbent can remove acid dyes of different structures.
Magnetic ...nanoparticles (MNPs) modified with aminoguanidine (AG) were synthesized and characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and infra-red spectra (IR). Adsorption of acid dyes onto this new adsorbent was further studied in terms of pH, contact time and initial dye concentration. Maximum adsorption capacity reached from pH 1.3 to 2.5 for different dyes. The adsorption can be better described by pseudo-second-order kinetic model compared to pseudo-first-order kinetic model. The adsorption behavior fits quite well with the Langmuir rather than the Freundlich model. The mean energy of adsorption (E) calculated from the Dubinin–Radushkevich (D–R) isotherm model confirmed the involvement of chemical adsorption. This adsorbent could remove acid dyes with different structures rapidly with high adsorption capacity. Moreover, the adsorbent possesses good reusability.
PDF
