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1.
Kalina Mambourg Laurie Bodart Nikolay Tumanov Steve Lanners Johan Wouters 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(3):205-211
The condensation reaction of 2‐mercapto‐3‐methoxybenzaldehyde with 3‐aminopyridine afforded an unexpected N‐alkylated [1,5]dithiocine instead of the N‐salicylideneaniline. The proposed mechanism for this condensation involves a strong intramolecular hydrogen bond between the thiol and the amine groups, leading to a second condensation. The corresponding product, i.e. 4,10‐dimethoxy‐13‐(pyridin‐3‐yl)‐6H,12H‐6,12‐epiminodibenzo[b,f][1,5]dithiocine methanol 0.463‐solvate, C21H18N2O2S2·0.463CH3OH, was characterized by single‐crystal X‐ray diffraction analysis. The supramolecular structure shows π–π stacking and S…S interactions in the crystal packing. Within the asymmetric unit, two geometries of the N atom are observed. Although a planar geometry should be expected, a pyramidal one is observed due to the crystal packing. The presence of the two geometries was further supported by density functional theory (DFT) calculations that show an electronic energy difference of less than 2 kJ mol?1 between the two conformers. 相似文献
2.
《Mendeleev Communications》2022,32(5):637-639
The cascade heterocyclization of 1,2-diamino-4-phenyl-imidazole with ethyl 2-arylidene-2-cyanoacetates affords 1,2,3,4-tetrahydroimidazo[1,5-b]pyridazine-3-carbonitrile derivatives as mixtures of diastereomers. The experimental data and quantum chemical calculations were used to propose processes. The three-component processing with above-mentioned diamine, ethyl cyanoacetate and aromatic aldehydes leads to the same products in generally lower yields. 相似文献
3.
A greener and efficient method for the synthesis of ynones and 1,3-diynes using copper oxide nanoparticles (CuONPs) doped reduced graphene oxide (CuO@rGO) catalyst under palladium, ligand and solvent free conditions have been developed. The catalyst was subsequently utilized for the synthesis of biologically active 1,5-benzodiazepines in one pot via sequential addition of acyl chlorides, terminal alkynes and o-phenylenediamines. The methodology initially involves in situ formation of ynones which react with o-phenylenediamines in presence of ethanol to afford a wide variety of benzodiazepines. Mild reaction conditions, good to an excellent yield of the products, cheap and recyclable catalyst make this methodology environmentally benign and sustainable. 相似文献
4.
Prof. Dr. Fa-Guang Zhang Xue-Qi Wang Yin Zhou Hong-Song Shi Zhe Feng Prof. Dr. Jun-An Ma Prof. Dr. Ilan Marek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15378-15396
Remote functionalization reactions have the power to transform a C−H (or C−C) bond at a distant position from a functional group. This Review summarizes recent advances and key breakthroughs in remote fluorination, trifluoromethylation, difluoromethylation, trifluoromethylthiolation, and fluoroalkenylation reactions. Several powerful strategies have emerged to control the reactivity and distal selectivity such as the undirected radical approach, the 1,5-hydrogen atom transfer, the metal migration, the use of distant directing groups, and the ring-opening reactions. These unconventional and predictable C−H (and C−C) functionalization transformations should allow for the preparation of a wide range of otherwise-difficult-to-access alkyl, aromatic, heteroaromatic, and structurally complex fluorides. 相似文献
5.
《印度化学会志》2023,100(4):100973
The antimicrobial resistance and excessive use of modern drugs has hampered the treatment of infectious disease. Therefore, the development of new antibiotics with very good efficacy and lesser side effects is the focused area of medicinal chemists. In the present work, the design and copper (I) catalyzed click synthesis of some amide linked binol based 1,4-disubstituted 1,2,3-bistriazole hybrids from bisalkyne precursor is reported along with characterization of the newly synthesized bistriazoles with the support of IR, NMR and HRMS spectral techniques. The in vitro antimicrobial screening of these bistriazoles against selected bacterial (S. aureus, B. subtilis, and E. coli) and fungal (A. niger and C. albicans) strains signifies the importance of amide and triazole moiety in the final derivatives. The in silico docking studies further supports the antimicrobial results through various binding interactions with binding energies of compound 6f (1KZN: 9.7 kcal/mol) and 6h (4WMZ: 13,3 kcal/mol). 相似文献
6.
《Arabian Journal of Chemistry》2023,16(5):104694
Copper(II)@polyimide linked covalent organic frameworks (Cu@PI-COF) under solvent-free and microwave assisted conditions have been used in an efficient one-pot protocol for the preparation of 1,5-benzodiazepines via 1,2-diaminobenzene, aromatic aldehydes and dimedone. By applying solvent-free conditions and microwave irradiation, three-component condensation provides safe operations, low pollution, quick access to products, and an easy set-up. As a result of its reusability, the catalyst can also be reutilized many runs without missing any activity. 相似文献
7.
High capacity and cycling stability of poly(diaminoanthraquinone) as an organic cathode for rechargeable lithium batteries 下载免费PDF全文
Yi Fei Shen Ding Ding Yuan Xin Ping Ai Han Xi Yang Min Zhou 《Journal of Polymer Science.Polymer Physics》2015,53(4):235-238
Poly(1,5‐diaminoanthraquinone) is synthesized by oxidative polymerization of diaminoanthraquinone monomers and investigated as an organic host for Li‐storage reaction. Benefiting from its high density of redox‐active, Li+‐associable benzoquinone groups attached to conducting polyaniline backbones, this polymer undergoes its cathodic reaction predominately through Li+‐insertion/extraction processes, delivering a very high reversible capacity of 285 mAh g?1. In addition, the PDAQ polymer cathode exhibits an excellent rate capability (125 mAh g?1 at 800 mA g?1) and a considerable cyclability with a capacity retention of ~160 mAh g?1 over 200 cycles, possibly serving as a sustainable, high capacity Li+ host cathode for Li‐ion batteries. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 235–238 相似文献
8.
Graphene field-effect transistors (GFET) have emerged as powerful detection platforms enabled by the advent of chemical vapor deposition (CVD) production of the unique atomically thin 2D material on a large scale. DNA aptamers, short target-specific oligonucleotides, are excellent sensor moieties for GFETs due to their strong affinity to graphene, relatively short chain-length, selectivity, and a high degree of analyte variability. However, the interaction between DNA and graphene is not fully understood, leading to questions about the structure of surface-bound DNA, including the morphology of DNA nanostructures and the nature of the electronic response seen from analyte binding. This review critically evaluates recent insights into the nature of the DNA graphene interaction and its affect on sensor viability for DNA, small molecules, and proteins with respect to previously established sensing methods. We first discuss the sorption of DNA to graphene to introduce the interactions and forces acting in DNA based GFET devices and how these forces can potentially affect the performance of increasingly popular DNA aptamers and even future DNA nanostructures as sensor substrates. Next, we discuss the novel use of GFETs to detect DNA and the underlying electronic phenomena that are typically used as benchmarks for characterizing the analyte response of these devices. Finally, we address the use of DNA aptamers to increase the selectivity of GFET sensors for small molecules and proteins and compare them with other, state of the art, detection methods. 相似文献
9.
Platinum‐Catalyzed Cascade Rearrangement Reaction of 1,5‐Diynyl Esters: Unusual Regioselective 1,5‐Hydride Migration 下载免费PDF全文
A highly regioselective sequential 1,3‐acyloxy migration/pentannulation/1,5‐hydride migration reaction is disclosed which provides an efficient access to (E)‐2‐vinyl‐3‐oxo‐1‐methyleneindenes under neutral and mild reaction conditions. The migrated hydrogen atom was derived from an unactivated alkyl group, and the long‐range 1,5‐H shift was confirmed through related deuterium experiments. 相似文献
10.
利用过渡金属镉(锌)盐与1,5-二(2-乙基咪唑)戊烷(BEIP)、5-羟基间苯二甲酸(5-OHH2IP)在水热条件下合成了配合物[Cd(BEIP)(Cl)2]n(1)和[Zn(BEIP)(5-OHIP)]n(2),并对其进行了元素分析、IR及X射线衍射法表征。晶体结构研究表明:配合物1属于正交晶系,Pca21空间群。配合物2属于单斜晶系,P21/n空间群,β=100.542(4)°。配合物1是由配体1,5-二(2-乙基咪唑)戊烷连接镉离子形成一维链状结构。而配合物2是由配体间苯二甲酸连接锌离子形成一维链状结构,该一维链通过1,5-二(2-乙基咪唑)戊烷连接成二维网络结构,进而通过氢键连接成三维超分子结构。此外,配合物1和2具有较高的稳定性和较好的荧光性能,配合物2对甲基橙染料有一定的降解作用。 相似文献