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1.
《Mendeleev Communications》2022,32(1):123-125
The synthesis, structure and properties of copper(II) perchlorate complexes with antipyrine (AP), [Cu(AP)4(H2O)](ClO4)2 and [Cu(AP)5](ClO4)2, are described and compared with those of alternative compounds containing different AP ligands. 相似文献
2.
本文合成了配合物[Cu(pcba)2·(phen)(H2O)] (pcba =对氯苯甲酸,phen = 1,10-邻菲罗啉),该配合物属于三斜晶系,P1空间群,晶胞参数为a=0.790 98(2) nm,b=1.072 40(4) nm,c=1.487 19(6) nm,α=100.613(3)°,β=95.239(3)°,γ=108.334(3)°,Z=2,Dc=1.638 g·cm-3,F(000)=582,最终结构残差因子R1=0.035 9,wR2=0.089 1。采用紫外及荧光研究了配合物和人血清蛋白(HSA)的相互作用方式。结果表明,配合物静态猝灭HSA荧光,可求得配合物与HSA的猝灭常数Ksv=2.35×105 L·mol-1,猝灭速率常数Kq=2.35×1013 L·mol-1·s-1,结合常数为Ka=2.14×1013 L·mol-1,结合位点n=2.37。同时,研究了配合物对胃癌细胞A549、宫颈癌细胞Hela和肝癌细胞HepG2的抗增殖能力。 相似文献
3.
电镀实验是电解原理应用的重要案例,通过实验不仅要获得定性的感性认知,还应该获得定量的理性数据。针对电镀铜实验,通过改变铜离子浓度、pH、电解时间、电解电压和电解温度等因素,探究其对镀层厚度、均匀性和致密性等性质的影响,在电解原理的基础上分析其形成机制,从而确定了电镀铜较适宜的操作条件,以此为学生开展电镀实验提供参考案例与研究思路。 相似文献
4.
声发射技术可以实现无氧铜切削加工特征的监测与评价。采用声发射技术监测单颗金刚石磨粒旋转切削无氧铜,利用G-P算法重构出声发射时域信号相空间,采用自相关函数法计算出相空间时间延迟参数,通过相空间双对数曲线的计算,得到不同切削工况下的关联维数。研究结果表明,进给速度和切削速度对声发射信号影响较不显著,切深与声发射信号振幅呈正效应关系;声发射信号双对数曲线呈现阶段性增加趋势,并逐渐收敛于饱和状态,关联维数随着嵌入维数的增加先快速下降后趋于平稳;金刚石切削无氧铜的声发射信号具有混沌运动变化特性,在较小嵌入维数时,关联维数与切深和切削速度呈现线性负效应关系,与进给速度呈现线性正效应关系。该研究为无氧铜的切削加工提供理论参考。 相似文献
5.
Enantioselective Copper‐Catalyzed Azide–Alkyne Click Cycloaddition to Desymmetrization of Maleimide‐Based Bis(alkynes) 下载免费PDF全文
Tao Song Dr. Li Li Dr. Wei Zhou Dr. Zhan‐Jiang Zheng Dr. Yuan Deng Dr. Zheng Xu Prof. Dr. Li‐Wen Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):554-558
A copper catalyst system derived from TaoPhos and CuF2 was used successfully for catalytic asymmetric Huisgen [3+2] cycloaddition of azides and alkynes to give optically pure products containing succinimide‐ and triazole‐substituted quaternary carbon stereogenic centers. The desired products were obtained in good yields (60–80 %) and 85:15 to >99:1 enantiomeric ratio (e.r.) in this click cycloaddition reaction. 相似文献
6.
In the presence of the inexpensive and non‐toxic polymethylhydrosiloxane, the combination of copper(II) acetate and a chiral diphosphine displayed high catalytic efficiency in the asymmetric hydrosilylation of a series of aromatic ketones in air atmosphere and at room temperature. (R)‐1‐Arylethanols were obtained with up to 99% yield and 93% enantiomeric excess. Meanwhile, the electron effect and steric hindrance of substituents on the aromatic ring had an interesting influence on both the yields and enantioselectivities. Furthermore, a possible mechanism was presented to explain the influence of some key factors on the reaction. 相似文献
7.
Highly Selective Copper‐Catalyzed Asymmetric [3+2] Cycloaddition of Azomethine Ylides with Acyclic 1,3‐Dienes 下载免费PDF全文
María González‐Esguevillas Ana Pascual‐Escudero Dr. Javier Adrio Prof. Dr. Juan C. Carretero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(12):4561-4565
The first examples of the catalytic asymmetric 1,3‐dipolar cycloaddition of azomethine ylides with acyclic activated 1,3‐dienes (and 1,3‐enynes) are described. Under copper catalysis, a selective cycloaddition at the terminal γ,δ‐C?C bond is observed. In addition, depending on the ligand used, either the exo or the endo adduct can be obtained with high selectivity. Under appropriate reaction conditions, the acyclic 1,6‐addition product is detected, suggesting a stepwise mechanism. The resulting C4‐alkenyl‐substituted pyrrolidines are suitable substrates for further access to polycyclic systems, as highlighted by the preparation of hexahydrochromeno[4,3‐b]pyrrole and the tetracyclic core of the alkaloid gracilamine. 相似文献
8.
Shyam Sundar Mondal Namita Jaiswal Partha Sarathi Bera Ranjay K. Tiwari Jogendra Nath Behera Nripen Chanda Subhas Ghosal Tanmoy Kumar Saha 《应用有机金属化学》2021,35(1)
A series of copper (II) ( 1 and 3 ) and cobalt (II/III) ( 2 , 4 and 5 ) complexes comprising different imino‐phenolate ligands DCH , DTH and DBH 2 (where DCH = 2,4‐dichloro‐6‐((mesitylimino)methyl)phenol, DTH = 2,4‐di‐tert‐butyl‐6‐((mesitylimino)methyl) phenol and DBH 2 = 2,4‐dibromo‐6‐((mesitylimino)methyl)phenol) have been prepared with excellent yield and high purity. By utilizing different spectroscopic tools such as UV–visible, electrospray ionization (ESI)‐mass, Fourier‐transform infrared (FTIR) spectrometry and elemental analysis, the prepared complexes ( 1 – 5 ) were thoroughly characterized. The molecular structure of the synthesized complexes was ascertained by using single‐crystal X‐ray diffraction studies (SCXRDs). The experiment reveals that Complexes 1 – 5 bind to calf thymus DNA (CT‐DNA) through non‐intercalative way with good interacting abilities. However, 1 – 5 are excellent quenchers of the fluorescence intensity of bovine serum albumin (BSA) following the static pathway. Additionally, they had shown remarkable cytotoxic potential against MCF‐7 (mammary gland adenocarcinoma) and A549 (lung adenocarcinoma) cell lines. The IC50 values associated with these complexes were much lower than the conventional drug cisplatin. Apoptosis‐induced cell death was confirmed from the DNA fragmentation studies and Hoechst 33342 staining. The 2′,7′‐dichlorofluorescein diacetate (DCFDA) assay indicates that the complex mediated reactive oxygen species (ROS) generation is accountable for governing the apoptosis mechanism via oxidative cell distress. Apart from these studies, by carrying out density functional theory (DFT) method, highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) energy gap calculations and optimized structures of the synthesized complexes were accomplished. 相似文献
9.
An efficient and practical route to β‐keto sulfones has been developed through heterogeneous oxidative coupling of oxime acetates with sodium sulfinates by using an MCM‐41‐supported Schiff base‐pyridine bidentate copper (II) complex [MCM‐41‐Sb,Py‐Cu (OAc)2] as the catalyst and oxime acetates as an internal oxidant, followed by hydrolysis. The reaction generates a variety of β‐keto sulfones in good to excellent yields. This new heterogeneous copper (II) catalyst can be easily prepared via a simple procedure from readily available and inexpensive reagents and exhibits the same catalytic activity as Cu (OAc)2. MCM‐41‐Sb,Py‐Cu (OAc)2 is also easy to recover and is recyclable up to eight times with almost consistent activity. 相似文献
10.
Dr. Hiromi Oshita Takashi Suzuki Kyohei Kawashima Prof. Dr. Hitoshi Abe Prof. Dr. Fumito Tani Prof. Dr. Seiji Mori Prof. Dr. Tatsuo Yajima Prof. Dr. Yuichi Shimazaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(32):7649-7658
In order to gain new insights into the effect of the π–π stacking interaction of the indole ring with the CuII–phenoxyl radical as seen in the active form of galactose oxidase, we have prepared a CuII complex of a methoxy-substituted salen-type ligand, containing a pendent indole ring on the dinitrogen chelate backbone, and characterized its one-electron-oxidized forms. The X-ray crystal structures of the oxidized CuII complex exhibited the π–π stacking interaction of the indole ring mainly with one of the two phenolate moieties. The phenolate moiety in close contact with the indole moiety showed the characteristic phenoxyl radical structural features, indicating that the indole ring favors the π–π stacking interaction with the phenoxyl radical. The UV/Vis/NIR spectra of the oxidized CuII complex with the pendent indole ring was significantly different from those of the complex without the side-chain indole ring, and the absorption and CD spectra exhibited a solvent dependence, which is in line with the phenoxyl radical–indole stacking interaction in solution. The other physicochemical results and theoretical calculations strongly support that the indole ring, as an electron donor, stabilizes the phenoxyl radical by the π–π stacking interaction. 相似文献