Solvent Atmosphere Research Articles

Using a New Pt(II) Source to Make Pt(II) Lantern‐Shaped Cages, Including Low‐Symmetry, Heteroleptic, and Multicavity Examples

Current synthetic methods towards Pt(II) lantern‐shaped cages involve the use of dry solvent, inert atmosphere, lengthy reaction times, and highly variable yields if isolated. Starting materials such as [Pt(CH3CN)4](BF4)2 suffer from a poor shelf‐life, reducing the synthetic accessibility of various Pt(II) architectures. A new Pt(II) source (with varied counterions), [Pt(3‐ClPy)4](X)2 (3‐ClPy = 3‐chloropyridine, X = BF4‐, OTf‐, NO3‐), is developed and characterised, showing greatly enhanced shelf‐life characteristics under ambient atmospheric conditions. Using this starting material, the assembly of Pt(II) lantern‐shaped cages was completed in as little as 1.5 hours with wet solvent and ambient atmosphere. The first examples of low‐symmetry, heteroleptic and multicavity Pt(II) lantern‐shaped cages are reported using this approach. Attempts towards an M6L8 octahedron using a tritopic ligand instead generate an interesting M2L4 cage with unbound pyridyl arms. Ligands and cages are characterised by NMR spectroscopy, IR spectroscopy, mass spectrometry, and X‐ray crystallography in some cases.

Using a NewPt(II) Source to Make Pt(II) Lantern-Shaped Cages, Including Low-Symmetry, Heteroleptic, and Multicavity Examples.

Current synthetic methods towards Pt(II) lantern-shaped cages involve the use of dry solvent, inert atmosphere, lengthy reaction times, and highly variable yields if isolated. Starting materials such as [Pt(CH3CN)4](BF4)2 suffer from a poor shelf-life, reducing the synthetic accessibility of various Pt(II) architectures. A new Pt(II) source (with varied counterions), [Pt(3-ClPy)4](X)2 (3-ClPy = 3-chloropyridine, X = BF4-, OTf-, NO3-), is developed and characterised, showing greatly enhanced shelf-life characteristics under ambient atmospheric conditions. Using this starting material, the assembly of Pt(II) lantern-shaped cages was completed in as little as 1.5 hours with wet solvent and ambient atmosphere. The first examples of low-symmetry, heteroleptic and multicavity Pt(II) lantern-shaped cages are reported using this approach. Attempts towards an M6L8 octahedron using a tritopic ligand instead generate an interesting M2L4 cage with unbound pyridyl arms. Ligands and cages are characterised by NMR spectroscopy, IR spectroscopy, mass spectrometry, and X-ray crystallography in some cases.

Solvent and Metal‐Ligand Co‐Assisted Synthesis of Self‐Supporting Ni‐Co‐Mo‐S Cross‐Linked Nanostructures for Supercapacitors

AbstractConstruction of prosperous morphology and incorporation of multiple metals with synergistic effect can effectively enhance the electrochemical performance of electrode materials. Herein, transition metal (Ni, Co, Mo) sulfides (NCM‐DI, NCM‐DI‐NTA, NCM‐EG, NCM‐EG‐NTA, NCM‐Mix‐NTA) were synthesized, and the morphology was adjusted by incorporating metal ligand and altering the solvent atmosphere. The addition of ligand nitrilotriacetic acid (NTA) endowed the formation of cross‐linked network (NCM‐DI‐NTA, NCM‐EG‐NTA, NCM‐Mix‐NTA), and the as‐prepared materials generated in mixed solvent (NCM‐Mix‐NTA) displayed smaller size. Materials with NTA added (NCM‐DI‐NTA, NCM‐EG‐NTA, NCM‐Mix‐NTA) displayed higher specific capacity (754, 943 and 1206 F g−1, respectively), which is much higher than NCM‐EG (909 F g−1) and NCM‐DI (331 F g−1). After doped with rGO, the materials (NCM‐Mix‐NTA‐rGO) exhibited a specific capacity of 1984 F g−1 at 1 A g−1. When assembled into asymmetric supercapacitors, it delivered the energy density of 61.6 Wh kg−1 at a power density of 901.4 W kg−1, and maintained the 86.5 % of their initial capacity even after 5000 cycles.

Visible Light-Induced Metal-free Arylation of Coumarin-3-carboxylates with Arylboronic Acids.

The present work represents a novel methodology for the selective arylation of coumarin-3-carboxylates with arylboronic acids via a photochemical route, marking the first-ever attempt for the direct alkenyl C-H arylation using rose bengal as a photocatalyst, which is a readily available and cost-effective alternative to transition metal catalysis. The reaction proceeds smoothly in MeOH/H2O solvent media in the presence of radical initiator affording the arylated products in good yields (60-80 %). The reaction parameters such as visible light, radical initiator, oxidant, anhydrous solvent, and inert atmosphere play a crucial role for the success of this methodology. The substituents present on the substrate show a significant effect on the conversion. This study provides a valuable contribution to the field of organic synthesis offering a new and efficient approach to the arylation of coumarin-3-carboxylic acid esters with a broad substrate scope and high functional group tolerance. It is a versatile method and provides a direct access to biologically relevant 4-arylcoumarin-3-carboxylates.

Surface Crystallization Modulation toward Highly-Oriented and Phase-Pure 2D Perovskite Solar Cells.

2D perovskites have shown great potential toward stable and efficient photovoltaic devices. However, the crystal orientation and phase impurity issues of 2D perovskite films originating from the anisotropic crystal structure and specific growth mechanism have demoted their optoelectronic performances. Here, the surface crystallization modulation technique is introduced to fabricate the high-quality 2D perovskite films with both vertical crystal orientation and high phase purity by regulating the crystallization dynamics. The solvent atmosphere condition is instituted during film processing, which promotes the formation of an oriented 2D perovskite layer in stoichiometric composition at the vapor-liquid interface and templates the subsequent film growth. The solar cells based on the optimized 2D perovskite films exhibit a power conversion efficiency of 15.04%, the record for 2D perovskites (with the perovskite slab thickness n ≤ 3 and high phase purity). The solar cells based on the highly-oriented and phase-pure 2D perovskite films also demonstrate excellent thermal and humidity stabilities.

Morphology Engineering of the Asymmetric PS-b-P4VP Block Copolymer: From Porous to Nanodot Oxide Structures.

In the present work, we demonstrate the formation of oxide porous and nanodot structures from the same block copolymer (BCP) by the phase inversion of a BCP template. We investigated the effect of solvent annealing time on the ordering of asymmetric, cylinder forming, polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) BCP. Phase separation of PS-b-P4VP was achieved by solvent vapor annealing (SVA) in a solvent atmosphere that is (partially) selective to P4VP to initially generate hexagonally arranged, cylindrical arrays of the expected structure. The morphology of the BCP changed from P4VP hexagonally packed cylinders to an 'inverse' structure with PS cylinders embedded in a P4VP matrix. This suggests that selective swelling occurs over time such that the swollen P4VP phase becomes the majority volume component. Metal ions (Ga3+, In3+) were infiltrated into the BCP templates by a solution-mediated infiltration approach, followed by an ultraviolet-ozone treatment to remove the polymer and oxidize the metallic ions to their oxides. The findings show that a single BCP can be used to create both metal oxide arrays and porous structures of metal oxides by simply varying the duration of the solvent annealing process. The resulting structures were analyzed through several methods including scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy, and energy-dispersive X-ray spectroscopy. XPS analyses confirmed the complete elimination of the BCP template and the presence of metal oxides. This study provides important insights into the development of functional BCP materials with inverse structures.

Straight Manipulation Annealing in a Solvent Atmosphere for Quality-Improved Cs2AgBiBr6 Perovskites.

As a new-generation photoelectric material, perovskites have attracted researchers' attention due to their excellent optoelectronic properties. However, the existence of defects inevitably causes structural degradation and restricts their performance, which need to be further improved by post-treatment. At present, post-treatments mostly focus on non-contact treatments, which may constrain the effect since the influence on the perovskites caused by the direct contact is much more straightly. Therefore, we proposed an annealing strategy of straight manipulation in a solvent atmosphere with the assistance of polyimide (PI) tape for the perovskite post-treatment, due to the high heat resistance and less glue residual of this tape. It casts an influence on the perovskite directly, proving the possibility of the straight manipulation by operators, promoting the recrystallization of the perovskite grains and removing the impurity substance. The optimized Pb-free perovskite film exhibits a better X-ray sensitivity of 7.5 × 104 μC Gyair-1 cm-2 and a great detection limit of 47 nGyair s-1, which is comparable to advanced Pb-based perovskite X-ray detectors and all commercial ones. The new annealing strategy provides a facile, effective, and simple method to improve the perovskite quality, exhibiting the potential and harmlessness of the direct contact post-treatment, which paves the way for a broader application of perovskites.

Molecular and silica-supported metal complexes as new catalysts for hydrosilylation

Two disiloxanes with pyridyl or isocyanide functional groups, as well as silica materials carrying pyridyl or thiol functionalities were used as ligands for Pt(IV) and Fe(III) ions. The molecular and silica-supported metal complexes were tested in a model hydrosilylation reaction between 1,3-divinyl tetramethyldisiloxane and 1,1,3,3-tetramethyldisiloxane, conducted in (pseudo)-heterogeneous conditions. The new hydrosilylation catalysts afforded 75-100 % conversion and 87-93 % selectivity, based on NMR data, while some of them presented recyclability; they were also successful in silicones crosslinking at room temperature. In particular, the iron-isocyanide disiloxane complex is proposed as a promising, cheap, unsophisticated and stable catalyst, capable to act in heterogeneous conditions, without the need of dry solvent or inert atmosphere. Silica-supported Pt or Pt/Pd catalysts, obtained with commercial or recovered noble metals precursors, presented high conversion and increased regioselectivity in the hydrosilylation reaction, being reusable, and are efficient in other hydrosilylation reactions, useful in organic and silicon chemistry.

Crazing Initiation and Growth in Polymethyl Methacrylate under Effects of Alcohol and Stress

Polymer crazing is typically a precursor to damage and considerably reduces the mechanical performance of polymer materials. The concentrated stress caused by machines and the solvent atmosphere created during machining exacerbates the formation of crazing. In this study, the tensile test method was employed to examine the initiation and progression of crazing. The research focused on polymethyl methacrylate (PMMA), both regular and oriented, and the impact of machining and alcohol solvents on the formation of crazing. The results showed that the alcohol solvent influenced PMMA through physical diffusion, whereas machining primarily affected crazing growth via residual stress. Treatment reduced the crazing stress threshold of PMMA from 20% to 35% and produced a threefold increase in its sensitivity to stress. The findings revealed that oriented PMMA exhibited 20 MPa higher resistance to crazing stress compared with regular PMMA. The results also indicated that the extension of the crazing tip and thickening were in conflict, with the crazing tip of regular PMMA severely bending under tensile stress. This study provides valuable insight into the initiation of crazing and the methods of its prevention.

Effects of residual dimethyl sulfoxide on the storage performance of nano-TATB

The stability of nano-TATB in an environment of long-term storage or service is currently one concern since it will affect the reliability of weapon systems. To explore the effects of the residual dimethyl sulfoxide (DMSO) solvent generated during synthesis on the storage performance of nano-TATB, this study proposed a new strategy that utilized solvent atmosphere induction to simulate the effects of residual solvents for the first time and quantified the residual solvents using the equilibrium adsorption capacity (Qe) obtained from the pseudo-first-order adsorption kinetic model. Moreover, this study investigated the storage performance of nano-TATB in the DMSO atmosphere using techniques of scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy (Raman), and infrared (IR) spectroscopy. The results show that the residual DMSO can induce nano-TATB growth more significantly than stimuli in a hot and humid environment. After aging at 60 ​°C for 1 ​d in the DMSO atmosphere, a large number of particles with relatively a regular shape and a particle size of about 1 ​μm were generated in the DMSO atmosphere, with a Qe of DMSO of (1.045 ​± ​0.026) mg·g−1. After aging for 5 ​d, some nano-TATB particles grew and had a particle size of up to 5–6 ​μm, and the average density and cohesive strength of nano-TATB greatly increased. As shown by the analysis of the growth mechanism of nano-TATB in the DMSO atmosphere based on the above experimental results, the main reason for the self-assembly of nano-TATB is the surface DMSO induction caused by the interactions between nano-TATB and DMSO molecules. These results show that the key to improving the storage stability of nano-TATB is to reduce the content of residual solvents.

Photocatalytic Activity of Triphenylphosphine and Potassium Iodide System in the Decarboxylative Alkylation of 3‐Cyanochromones

AbstractThe photocatalytic decarboxylative alkylation of 3‐cyanochromones using triphenylphosphine and potassium iodide as photoredox‐mediators has been described. The lower price of potassium iodide and triphenylphosphine, compared to standard photocatalysts, make this method cost‐effective and interesting. Visible light, cheap and readily available substrates, anhydrous solvent and inert atmosphere constitute the key parameters for the success of the developed transformation. The developed approach allows for obtaining a number of biologically relevant products with very good yields and benefits from a broad scope.

Ultrafine Palladium Embedded in N‐doped Porous Carbon Material from Carbazole‐covalent Triazine Polymer for Green Suzuki‐Miyaura Coupling Reaction

AbstractHere, we develop a facile synthesis route to fabricate ultrafine palladium nanoparticles embedded in N‐doped porous carbon material (Pd@N‐PCM), in which carbazole‐covalent triazine polymers obtained by Friedel‐Crafts alkylation at room temperature are used as precursor of N‐doped carbon. The obtained Pd@N‐PCM as a green catalyst shows the high catalytic efficiency (TOF=982 h−1) for Suzuki‐Miyaura coupling reaction of chlorobenzene under the mild reaction condition (room temperature, a non‐toxic solvent and air atmosphere). The brilliant catalytic activity of Pd@N‐PCM gives the credit to the concerted effect from the ultrafine Pd and N‐doped porous carbon.

Visible Light-Driven Reductive Azaarylation of Coumarin-3-carboxylic Acids.

In the manuscript, reductive and decarboxylative azaarylation of coumarin-3-carboxylic acids is described. It utilizes the photocatalytic activation of (cyano)azaarenes in the presence of fac-Ir(ppy)3 as a photocatalyst. The methodology is versatile and provides access to biologically relevant 4-substituted-chroman-2-ones. Visible light, photoredox catalyst, base, anhydrous solvent, and inert atmosphere constitute key parameters for the success of the described strategy. The developed methodology involves a wide range of coumarin-3-carboxylic acids as well as (cyano)azaarenes.

Solvent and Ionic Atmosphere Effects in Anion-π Interactions: Complexes of Halide Anions with p-Benzoquinones.

The interplay between the solvent polarity and ionic atmosphere in anion-π association was evaluated via an experimental and a computational study of the BQ·X- complexes between benzoquinones (BQ) and halide anions (X-). The UV-Vis spectral measurements showed that these complexes are characterized by the strong absorption bands in the 300-450 nm range and their effective formation constants, Keff, measured in dichloromethane in the absence (or at low concentrations) of the supporting electrolyte, Bu4NPF6, were higher than those in acetonitrile. The experimental data were consistent with the results of the computations, which showed that magnitudes of the interaction energy, ΔE, between BQ and X- decreased considerably with the increase in the polarity of the media. The addition of auxiliary electrolytes (e.g., Bu4NPF6) led to a decrease in the concentration of the BQ·X- complexes. These changes were related to the competing associations of the π-acceptors with halides and PF6- anions (since the interaction energies between BQ acceptors and common non-halide anions, e.g., PF6-, BF4-, and NO3-, were comparable to those in the BQ·X- complexes) and to the increased ionic strength of the solutions. The variations in strength of anion-π interactions with the solvent polarity and ionic atmosphere were related to the higher effective ionic radii of the complexes. Due to the larger effects of the auxiliary electrolytes in dichloromethane, the formation constants for the BQ·X- complexes measured at high ionic strength in this solvent were lower than those in more polar acetonitrile or propylene carbonate. Such a combination of the effects of the solvent and ionic atmosphere should be taken into account when comparing experimental data with the results of the calculations and in design of the systems for molecular recognition and catalysis.

Synthesis, spectral analysis, antibacterial activity, quantum chemical studies and supporting molecular docking of Schiff base (E)-4-((4-bromobenzylidene) amino)benzenesulfonamide

A new Schiff base (E)-4-((4-bromobenzylidene) amino) benzenesulfonamide (M2) was synthesized by the reaction between 4-bromobenzaldehyde and sulfanilamide followed by characterization using IR, Raman, UV–Visible, 1HNMR, and 13CNMR spectral techniques. This was followed by electronic structure studies using DFT and TD-DFT. We simulated the IR spectrum using B3LYP/6-31+G(d,p) level of theory, followed by a comparison with experimental spectra and detailed potential energy distribution and vibrational assignment analysis. The comparison of experimental UV and simulated UV spectrum using TD-DFT B3LYP/6-31+G(d,p) in DMSO solvent atmosphere gave good agreement. As Schiff bases are biologically active, we checked for the potential activity of the synthesized compound with the help of ADMET prediction and found it to be active. Wavefunctions related properties like ELF, LOL, and ELF are also reported. Prediction of biological activity spectrum study indicated possible antibacterial activity against bacteria, which is supported by molecular docking against Staphylococcus aureus (3U2D) protein with a docking score of −7.1 kcal/mol. Experimental antibacterial study using the compound and standard drugs confirmed this prediction.

Effect of solvent on the adsorption behavior of asphaltene on silica surface: A molecular dynamic simulation study

In recent years, the hybrid thermal-solvent process has been widely applied to improve the recovery performance of steam injection processes in heavy oil reservoirs. In this paper, the method of Molecular Dynamics (MD) simulation is employed to illuminate the asphaltenes adsorption behavior in the thermal-solvent recovery process. Three different solvent molecules (CO2, C3H8, and nC4H10) and SARA (Saturates, Aromatics, Resins, Asphaltenes) simulated heavy oil model are constructed as the basic simulation model. A series of MD simulations at different temperature conditions are performed. Results show that for the SARA model, the asphaltene molecules can interact with the silica by a T-shape stacking, finally forming the asphaltene dense aggregates as a basic heavy oil occurrence state. The steric hindrance effect of other SARA components can also contribute to this configuration. Temperature significantly affects the adsorption configuration of asphaltenes by disassembling the dense core and loosening the structure of the aggregates. For the SARA model in three solvent atmospheres, the increasing temperature can benefit the extraction of light components. CO2 can only extract saturates, while nC4H10 and C3H8 can simultaneously extract the saturates and aromatics. Besides, asphaltenes re-precipitation behavior can be observed in the 393 K CO2 atmosphere. Both nC4H10 and C3H8 have mutual solubility with the heavy oil system. No apparent precipitation of asphaltenes occurs in the above two atmospheres. Comparing the performance of extraction capability and diffusion capability in all MD simulations, the nC4H10 can both extract light oil components and control the asphaltenes precipitation. It further reveals that nC4H10 can recover heavy oil more efficiently at a microcosm level. Among the three different solvents, nC4H10 is the optimal solvent for hybrid thermal-solvent processes in heavy oil reservoirs.

A solvent driven dual responsive actuator based on MOF/polymer composite

The dual-responsive actuator which response to external stimulus with deformation and discoloration simultaneously gained considerable attention for their application such as soft robot. Inspired by the soft MOF (Metal-Organic framework)/polymer solvent driven actuator based on flexible MOF which can expand/contract with the gain and loss of solvent molecules, and also the structural color films with inverted opal structure, a monolayer solvent driven dual-responsive actuator based on MOF/polymer composite, namely MIL-88A/CB(carbon black)/PVDF, has been successfully prepared through the casting and etching method. The MIL-88A/CB/PVDF film can respond to the change of ambient solvent atmosphere with the whole or part of the composite film exhibiting a synergistic coupling of the surface color change and the out-of-plane motion under the driven of the methanol vapor. The bending deformation of 730° can be quickly achieved in about 1.66 s and the color change covers a wide range with three high saturation color (red, green and blue) which can be observed with different view angles. In addition, some simple devices including smart flower, inchworm walker, and visual gas sensor were designed based on this material. This work is the first example which apply MOF to solvent driven dual response materials with simultaneous deformation and discoloration, which opens up a new application field for MOF, and also provides a new perspective for the preparation of smart materials.

Schiff base (Z)-4-((furan-2-ylmethylene)amino) benzenesulfonamide: Synthesis, solvent interactions through hydrogen bond, structural and spectral properties, quantum chemical modeling and biological studies

A new Schiff base (Z)-4-((furan-2-ylmethylene)amino)benzenesulfonamide (FURNI) was synthesized by the reaction reaction between furfural and sulfanilamide followed by characterization using IR, UV–Visible, 1HNMR, and 13CNMR spectral techniques. This was followed by electronic structure studies using DFT and TD-DFT. We simulated the IR spectrum using B3LYP/aug-ccPVDZ level of theory, followed by a comparison with experimental spectra and detailed potential energy distribution and vibrational assignment analysis. The comparison of experimental UV and simulated UV spectrum using TD-DFT CAM-B3LYP/ aug-ccPVDZ in DMSO solvent atmosphere gave good agreement. The compound is found to interact with the solvent water molecule. Energy decomposition analysis showed that there exists a strong hydrogen bond between the compound and the solvent water. As Schiff bases are biologically active, we checked for the potential activity of the synthesized compound with the help of ADMET prediction and found it to be active. Wavefunctions related properties like ELF, ALIE, LOL, and ELF are also reported. Prediction of biological activity spectrum study indicated possible antimicrobial activity against bacteria and fungus, which is supported by molecular docking against human mitochondrial (2WYA) protein with a docking score of −7.2 kcal/mol. Experimental antibacterial and antifungal studies using the compound and standard drugs confirmed this prediction.

Structural, spectral elucidation, wavefunctional properties, natural bond orbitals, and molecular docking analysis of synthesized 1-phenyl-3(4-methoxyphenyl)-2-propenone: protease kinase inhibitor

In this present work, structural, spectral, and electronic properties of newly synthesized 1-phenyl-3(4-methoxyphenyl)-2-propenone compounds are examined by making the use of the density functional theory Gaussian 16 W tool. Optimized structural parameters, topological properties (Electron localization function and Localized orbital locators) are investigated in the aqueous phase. Experimental spectroscopic (Fourier transform infrared spectroscopy and Fourier transform Raman spectroscopy) investigation and quantum chemical analysis are performed on the title compound. Non-covalent interaction analysis is performed in different solutions. Bandgap energies are calculated from molecular orbital energies in various solvent atmospheres. Electrophilic site strength of headline compound is identified and analyzed from molecular electrostatic potential surface and Mulliken atomic charges analysis in different polar and non-polar liquids. Experimental and theoretical chemical shift values are recorded and predicted in a nonpolar solvent by Nuclear magnetic resonance spectral investigation. Hyperconjucative interactions are studied from the natural bond orbitals method. Drug likeness and mol inspiration properties are calculated. Moreover, a Molecular docking study is performed with breast cancer and anti-malarial receptors.

A Generic Protocol for Highly Reproducible Manufacturing of Efficient Perovskite Light‐Emitting Diodes Using In‐Situ Photoluminescence Monitoring

AbstractHalide perovskite light‐emitting diodes (PLEDs) have raised considerable attention due to their high color purity and rapid development performance. Although high‐efficiency PLEDs have been continuously and repeatedly reported, the lack of a highly reproducible manufacturing process for PLEDs hinders their future development and commercialization. Here, a generic protocol for rational control of the nucleation and crystallization process of the perovskite emission layer is reported. Through the monitoring of the photoluminescence during spin‐coating, the antisolvent dripping time can be precisely determined. Therefore, it is possible to repeatedly produce a perovskite emission layer with high PLQY, smooth surface/interface, and good homogeneity. As a result, high‐performance PLEDs are easily obtained. Moreover, the standard deviation of the fabricated PLEDs performance is smaller than 0.8%, showing high reproducibility independent of the process conditions such as the process temperature, solvent atmosphere, and spin‐coating parameters, which highlights the statement of the importance of rationally control of the antisolvent process. The methodology provides important progress towards highly reproducible manufacturing of PLEDs for practical applications.