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Dr. Pirudhan Karak P. A. Sreelakshmi Barsha Chakraborty Manisha Pal Bitasik Khatua Dr. Apurba Lal Koner Dr. Joyanta Choudhury 《Angewandte Chemie (International ed. in English)》2023,62(41):e202310603
Triazoles are an important class of compounds with widespread applications. Functionalization of the triazole backbone is thus of significant interest. In comparison to 1,2,3-triazoles, C−H activation-functionalization of the congeners 1,2,4-triazoles is surprisingly underdeveloped. Indeed, no such C−H activation-functionalization has been reported for 4-substituted 1,2,4-triazole cores. Furthermore, although denitrogenative ring-opening of 1,2,3-triazoles is well-explored, 1,2,4-triazole/triazolium substrates have not been known to exhibit N−N bond-cleaving ring-opening reactivity so far. In this work, we unveiled an unusual hidden reactivity of the 1,2,4-triazole backbone involving the elusive N−N bond-cleaving ring-opening reaction. This new reactivity was induced by a Satoh-Miura-type C−H activation-annulation at the 1,2,4-triazole motif appended with a pyridine directing group. This unique reaction allowed ready access to a novel class of unsymmetrically substituted 2,2′-dipyridylamines, with one pyridine ring fully-substituted with alkyl groups. The unsymmetrical 2,2′-dipyridylamines were utilized to access unsymmetrical boron-aza-dipyridylmethene fluorescent dyes. Empowered with desirable optical/physical properties such as large Stokes shifts and suitable hydrophobicity arising from optimal alkyl chain length at the fully-substituted pyridine-ring, these dyes were used for intracellular lipid droplet-selective imaging studies, which provided useful information toward designing suitable lipid droplet-selective imaging probes for biomedical applications. 相似文献
3.
Dr. Anoop Kumar Kushwaha Sushri Soumya Jena Dr. Mihir Ranjan Sahoo Dr. Debashish Das Prof. Saroj Kumar Nayak 《Chemphyschem》2023,24(18):e202300032
High-voltage alkali metal-ion batteries (AMIBs) require a non-hazardous, low-cost, and highly stable electrolyte with a large operating potential and rapid ion conductivity. Here, we have reported a halogen-free high-voltage electrolyte based on SiB11(BO)12−. Because of the weak π-orbital interaction of −BO as well as the mixed covalent and ionic interaction between SiB11-cage and −BO ligand, SiB11(BO)12− has colossal stability. SiB11(BO)12− possesses extremely high vertical detachment energy (9.95 eV), anodic voltage limit (∼10.05 V), and electrochemical stability window (∼9.95 V). Furthermore, SiB11(BO)12− is thermodynamically stable at high temperatures, and its large size allows for faster cation movement. The alkali salts MSiB11(BO)12 (M=Li, Na, and K) are easily dissociated into ionic components. Electrolytes based on SiB11(BO)12− greatly outperform commercial electrolytes. In short, SiB11(BO)12−-based compound is demonstrated to be a high-voltage electrolyte for AMIBs. 相似文献
4.
A parametric investigation of the friction performance of PC‐ABS parts processed by FDM additive manufacturing process 下载免费PDF全文
The friction performance is an important factor of parts processed by fused deposition modeling (FDM) for various engineering applications. It is one type of failure made of surface contact. The proper use of FDM process parameters can bring a significant reduction in friction and the amount of wear, thereby leading to a reduction in the material waste. To date, very little studies have been performed in this area. This paper investigates the effect of FDM manufacturing parameters on the friction performance of polycarbonate‐acrylonitrile butadiene styrene prototypes processed by FDM using definitive screening design and partial least squares method. The observation of surface morphology was obtained by the scanning electron microscopy to examine the effect of process parameters on the microstructure. The experimental results have shown that layer thickness, air gap, raster angle, and build orientation are the most influential factors affecting the friction performance of FDM manufactured parts. The proposed approach presented in this study provides an impetus to develop analytical modeling and functional relationships between FDM manufacturing parameters and friction performance. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
5.
An efficient [4+2] cyclization of N-methylanilines with maleimides to afford tetrahydroquinolines using N-hydroxyphthalimide as a metal-free and cheap organophotoredox catalyst is reported. The protocol involves C(sp3)H activation of N-methylanilines for the formation of α-amino radical without an oxidant at room temperature. The present method describes an easy preparation of tricyclic heterocycles in good to excellent yields under mild reaction conditions. 相似文献
6.
Muhammad Saad Khan Cornelius Borecho Bavoh Khor Siak Foo Azmi Mohd Shariff Zamzila Kassim Nurzatil Aqmar Bt Othman Bhajan Lal Iqbal Ahmed Mohammad Azizur Rahman Sina Rezaei Gomari 《Molecules (Basel, Switzerland)》2021,26(2)
This study evaluates the kinetic hydrate inhibition (KHI) performance of four quaternary ammonium hydroxides (QAH) on mixed CH4 + CO2 hydrate systems. The studied QAHs are; tetraethylammonium hydroxide (TEAOH), tetrabutylammonium hydroxide (TBAOH), tetramethylammonium hydroxide (TMAOH), and tetrapropylammonium hydroxide (TPrAOH). The test was performed in a high-pressure hydrate reactor at temperatures of 274.0 K and 277.0 K, and a concentration of 1 wt.% using the isochoric cooling method. The kinetics results suggest that all the QAHs potentially delayed mixed CH4 + CO2 hydrates formation due to their steric hindrance abilities. The presence of QAHs reduced hydrate formation risk than the conventional hydrate inhibitor, PVP, at higher subcooling conditions. The findings indicate that increasing QAHs alkyl chain lengths increase their kinetic hydrate inhibition efficacies due to better surface adsorption abilities. QAHs with longer chain lengths have lesser amounts of solute particles to prevent hydrate formation. The outcomes of this study contribute significantly to current efforts to control gas hydrate formation in offshore petroleum pipelines. 相似文献
7.
Patel Urvi Girme Aboli Patel Kalpana Ghule Chetana Hingorani Lal Gandhi Tejal 《平面色谱法杂志一现代薄层色谱法》2021,34(3):217-228
JPC – Journal of Planar Chromatography – Modern TLC - The objective of the present work was to develop a simple, specific, and fast high-performance thin-layer chromatographic (HPTLC)... 相似文献
8.
In this paper, Lipschitz class of two-variables is considered. This is the genralization of well-known Lipschitz class of functions. A new estimator of functions belonging to generalized Lipschitz class has been obtained. Also, the solutions for the Fokker-Planck equations have been obtained for two different cases by two-dimensional Legendre wavelet operational matrix method. The approximated solutions of the time-and space-Fokker Planck equation have been compared with the exact solutions and the solutions obtained by homotopy perturbation method. The proposed scheme is simple, effective and suitable for the solution of Fokker-Planck equation.
相似文献9.
Purnanand P. D. Shakya Shefali Saxena M. Sharma Basant Lal 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1093-1099
Based on 31 P NMR studies of thionyl chloride reaction with dialkyl alkylphosphonothionates, a method for preparation of alkylphosphonic dichloride has been investigated. A mechanism via intermediacy of ester chloride is suggested. 相似文献
10.
Jitender Gaur Shilpa Jain Rohit Bhatia Arun Lal Narender Kumar Kaushik 《Journal of Thermal Analysis and Calorimetry》2013,112(2):1137-1143
We demonstrate synthesis of water insoluble, novel copolymer PA1 from condensation of glyoxal dihydrazone and glyoxal dihydrazone bis(dithiocarbamate) monomers having high capacity to remove metal ions from aqueous solution. The presence of a high atomic percentage of nitrogen and sulfur atoms in PA1 leads to strong ligating ability with metal ions. The monomers and the polymer have been characterized by FTIR, UV–Visible spectroscopy, CHNS elemental analysis, NMR, MALDI-MS, and TG/DTA. As a proof of concept, the PA1 is tested for its ability to remove heavy metal ions Cu2+, Co2+, Fe2+, Ni2+, Mn2+, and CrO 7 2? from aqueous solutions. PA1 efficiently removed metals ions from the metal solutions. The highest absorption ability has been observed toward the iron salts where 0.969 g metal salt is absorbed by 1 g polymer. This study has implication for inexpensive and efficient polymer for purification of water. 相似文献