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951.
The title complex has been synthesized by the reaction of silicotungstic acid, 1,10-phenanthroline (phen) monohydrate and cupric acetate. The crystal structure belongs to triclinic system, space group P1 with a=1.158 46(15) nm, b=1.658 8(2) nm, c=1.664 4(2) nm, α=82.090(2)°, β=76.001(2)°, γ=86.531(2)°, and V=3.072 6(7) nm3, Dc=3.887 g·cm-3, Z=2, F(000)=3 196. R1=0.086 7, wR2=0.185 8. The structure shows that the copper(Ⅱ) atom is coordinated with two nitrogen atoms from the one phen and three oxgygen atoms from three water, forming a distorted square-pyramid configuration The cyclic voltametric behavior of the complex is also reported. CCDC: 298807. 相似文献
952.
Enantioselective Addition of Phenylacetylene to Aldehydes Catalyzed by Polymer-Supported Sulfonamide
Enantioselective formation of C-C bonds is an area of intense research. Among them, the asymmetric addition of alkynyl reagents to aldehydes is very useful for the synthesis of chiral secondary propargyl alcohols.[1] Recently, many significant homogeneous chiral ligands have been disclosed,[2,3] but very few efficient heterogeneous catalysts have been reported. Herein, we report our research results in the asymmetric addition of phenylacetylene to aldehydes catalyzed by polymer-supported chiral sulfonamide. 相似文献
953.
Surface modification of poly [1-(trimethylsilyl)-1-propyne] (PTMSP) membranes bybromine vapor has been studied. It is shown that Br/C atomic ratio at the surfaces increased withthe time of bromination until about 60 min, then it reached a plateau. The results of XPS and IRstudies indicated that the addition of bromine to double bonds and the replacement of H on CH_3 bybromine had taken place so that a new peak at 286.0 eV (C--Br)in C_(1s) spectra and some newbands, e. g. at 1220 and 580cm~(-1) in IR spectra were formed. The fact,t Po_2, permeability ofoxygen, decreased and α_(O_2/N_2), separation factor of oxygen relative to nitrogen, increased withbromination time, shows that surface modification of PTMSP by bromine may be an efficient approach to prepare PTMSP membranes used for practical gas separations. 相似文献
954.
镇元素簇合物是人们最感兴趣的簇合物之一l‘-’].已有的。作主要是研究它的稳定性和电子结构,对其成键性质还研究得不多·为止匕我们对Lkin为元素簇合物中所含原子个数,e为该化合物的电荷)进行了定域化研究,并得出一些有意义的结果·1计算我4rl采用GAMESS90程序m,在4-31G基组下进行了正则分子轨道SCFi十算(闭壳层采用RHF,开壳层采用UHF).然后,以QSU90程序问,用B0yS方法进行了定域化计算,得到定域分子轨道(LM),再根据LMO的系数和集居数分析,判断各分子中原子的成键情况问.共计算了18个簇合物.它们的原子数… 相似文献
955.
四配位硅单体及其共聚物的制备和结构表征 总被引:4,自引:0,他引:4
研究了直接从无定形二氧化硅出发, 与乙二醇、氢氧化钾反应, 生成高反应活性的五配位硅钾化合物, 并以此为原料与含活泼氯的3-氯丙烯反应制备出含双键官能团的四配位硅单体. 讨论了合成单体的条件如温度、反应时间、反应物浓度、溶液pH值及溶剂等因素的影响. 然后以该四配位硅单体与甲基丙烯酸甲酯(MMA)在偶氮二异丁腈(AIBN)作引发剂下进行自由基聚合得到支链含硅共聚物. 并借助于红外光谱(IR)、核磁共振(13C和1H, 29Si)、能谱元素分析对合成的单体进行了结构表征; 用红外光谱(IR)、热失重谱(TG)、差示扫描量热谱(DSC)、凝胶渗透色谱法(GPC)等现代测试手段对支链含硅共聚物进行了结构表征及热性能分析. IR表明四配位硅单体在1646 cm-1处是C=C的伸缩振动吸收峰, 在共聚物中此峰消失; TG表明共聚物在249.6 ℃才开始失重, 552 ℃有机部分失重完毕; GPC分析表明共聚物的数均分子量为8.7万. 相似文献
956.
Wen J. Mei Ying X. Liu Jie Liu Jun Li Kang C. Zheng Liang N. Ji 《Transition Metal Chemistry》2005,30(1):82-88
Two mixed porphyrin–polypyridyl RuII complexes [Ru(bpy)2(MPyTPP)Cl]Cl (1) and [Ru(phen)2(MPyTPP)Cl]Cl (
2
) (bpy=2,2-bipyridine; phen=1,10-phenanthroline; MPyTPP=5-monopyridyl-10,15,20–triphenylporphyrin) have been synthesized and characterized by elementary analysis, e.s.–m.s., cyclic voltammetry and u.v.–vis. spectroscopy. The DNA-binding properties of these complexes were investigated by electronic spectra, c.d. spectra and viscosity experiments. The results suggested that both complexes (1) and (2) bind to DNA in an outside binding mode. At the same time, theoretical calculations applying the ab initio and the density functional theory (DFT) methods were also performed, and the results showed that there is no good planarity on the main ligand MPyTPP of these complexes, and there are rather great distortion angles (dihedral angles ca. 72°) between the porphrin ring and each of the 10-, 15-, 20-phenyl groups. This may be the reason why the complexes bind to DNA in an outside mode, instead of an intercalative mode. 相似文献
957.
The complex [Cd(tren)(meim)](ClO4)2 was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in monoclinic system, space group P21/m with a=0.786 8(2) nm, b=0.834 2(2) nm, c=1.496 2(4) nm, Mr=538.64, Z=2, F(000)=542, Dc=1.822 g·cm-3, T=298(2) K, μ=1.435 mm-1 and λ=0.071 073 nm. The structure was refined to R=0.045 8 and wR=0.123 1 for 1 489 observed reflections with I>2σ(I). The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method. It was found to be active against the four test bacterial organisms. CCDC: 600198. 相似文献
958.
Jian‐Hua Zhao Hsuan‐Liang Liu Hsin‐Yi Lin Chih‐Hung Huang Hsu‐Wei Fang Shau‐Wei Tsai 《中国化学会会志》2007,54(4):835-842
In this study, we present the results from the semiempirical molecular orbital calculations for the acylation step in the lipase‐catalyzed ester hydrolysis. The results reveal that the lowest energy path for the formation of the tetrahedral intermediate is for the serine residue of the catalytic triad to attack the substrate, followed by coupling heavy atom movement and proton transfer. The calculations of four active site models show that the cooperation of the aspartate group and the oxyanion hole is capable of lowering the activation energy by about 16 kcalmol?1. Our results further suggest that the lipase‐catalyzed ester hydrolysis adopts the single proton transfer mechanism. 相似文献
959.
An efficient palladium-catalyzed Stille cross-coupling reaction has been developed. In the presence of 3 mol% of Pd(dba)2 and 6 mol% of DAB-Cy (1,4-dicyclohexyl-diazabutadiene), various aryl halides (iodides and bromides) were coupled with organotin compounds to afford the corresponding biaryls and alkyne in good to excellent yields. Furthermore, high TONs [turnover numbers, TONs up to 950,000 for the reaction of 1-iodo-4-nitrobenzene and tributyl(phenyl)stannane] for the Stille cross-coupling reaction were observed. 相似文献
960.
锂离子电池PMMA-VAc聚合物电解质的制备与性质研究 总被引:5,自引:0,他引:5
以甲基丙烯酸甲酯(MMA)和醋酸乙烯酯(VAc)为单体, 用乳液聚合法合成聚甲基丙烯酸甲酯-醋酸乙烯酯聚合物(PMMA-VAc), 并以此聚合物制备了新型聚烯烃膜支撑的聚合物膜及聚合物电解质. 用红外光谱(FTIR)、凝胶色谱(GPC)、差热和热重分析(DSC/TG)、扫描电镜(SEM)及电池充放电实验等方法研究了聚合物、聚合物膜和聚合物电解质的性质. 红外光谱结果表明, MMA与VAc通过各自的C=C双键打开聚合成PMMA-VAc. PMMA-VAc易于分散在混合碳酸酯溶剂中并形成凝胶, 凝胶粘度随PMMA-VAc浓度的增加而增加, 当浓度为4%时成膜效果最佳. PMMA-VAc膜具有大量的微孔结构, 具有极强的吸液性能. PMMA-VAc膜具有良好的热稳定性: 在380 ℃范围内保持稳定. 聚烯烃膜支撑的PMMA-VAc膜室温下的离子电导率为1.85×10-3 S•cm-1, 用作为锂离子电池的聚合物电解质时, 电池具有良好的循环稳定性和倍率性能. 相似文献