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研究了不同pH值下ZrEDTA配合物^1HNMR谱的温度依赖性,结果显示:pH=1.5和pH=6.8时配合物乙羧基质子都为1组AB谱,温度升高谱图无融合现象;而pH=5.0时配合物乙羧基质子呈现2组AB谱,且随温度升高出现融合现象.AB谱融合现象由△=∧迁移过程引起,通过全线型分析求得了速率常数及相关热力学参数。  相似文献   

3.
本文用常温方法合成了钯配合物,化学式[Pd(phen)(L-asp)]•3H2O,并用元素分析和红外图谱的方法进行分析,经单晶X射线衍射对其结构表征。以顺铂为参照,研究了该配合物对三种不同癌细胞(人宫颈癌细胞,肝癌细胞,口腔癌细胞)的细胞毒素作用,结果证明该钯配合物对人宫颈癌细胞有较强的抑制作用。通过多种光谱手段同时研究了该配合物与鱼精DNA作用模式,结果说明通过插入方式阻断鱼精DNA的复制。同时,测定配合物与pBR322质粒DNA作用的凝胶电泳。  相似文献   

4.
报道了苯硫酚为配体的五种顺磁性过渡金属簇合物的^1H NMR谱,简单讨论了产生各向同性位移机制及金属之间反铁磁偶合作用。  相似文献   

5.
本工作合成了一系列十个新的零价钯混配配合物,并对这些配合物进行了表征.研究了配体的立体效应和电子效应的差别,讨论了配体间的相互作用.  相似文献   

6.
姜波  魏冬  范九良  汪佳凤  周双生 《合成化学》2012,20(4):430-433,457
以姜黄素为原料,合成了二乙酰姜黄素(H2L)及其铜(Ⅱ)和铂(Ⅱ)配合物(CuL2和PtL2),其结构经1H NMR,IR,MS和元素分析确认。采用UV-Vis测定法和循环伏安法研究了CuL2和PtL2与ctDNA的相互作用。结果表明,CuL2和PtL2与ctDNA的作用属嵌插作用模式。  相似文献   

7.
合成和表征了1个新的钌(Ⅱ)配合物[Ru(bpy)2(dpapz)](ClO4)2,其中bpy=2,2'-联吡啶,dpapz=联吡啶并[3,2-a:2,'3-'c]-6-氮杂-吩嗪.通过紫外可见光谱、荧光光谱、与溴化乙锭的竞争键合实验和粘度测量研究了该配合物与小牛胸腺DNA的键合性质,并研究了该配合物的紫外可见光谱和荧光光谱的溶剂变色性质.结果表明,该配合物是具有键合常数Kb=6.9×105L/mol(50mmol/LNaCl)的DNA嵌入键合试剂和优良的荧光溶剂传感分子.  相似文献   

8.
本工作合成了一系列十个新的零价钯混配配合物,并对这些配合物进行了表征.研究了配体的立体效应和电子效应的差别,讨论了配体间的相互作用.一.配合物的合成与组成据文献合成dba(PhCH=CHCOCH=CHPh)和Pd_2(dba)_3(CHCl_3).其余试剂及溶剂均为市售商品,用前经无水无氧处理.  相似文献   

9.
合成了双安息香缩三乙四胺及其与草酸共同配位的Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)的三元双核金属配合物.经质谱、红外光谱、元素分析、摩尔电导与磁矩测定及热分析等方法表征.用气体吸收装置探讨了配合物在DMF溶剂中的载氧性质和载氧动力学.  相似文献   

10.
报道11中含R_2NCS_2配体的过渡金属配合物的~1HNMR研究结果。对其顺磁性化合物的磁性和电子结构进行了讨论;并探讨了抗磁性化合物的分子结构和NMR关系。  相似文献   

11.
蓝蓉  李浩然  韩世钧 《物理化学学报》2005,21(11):1295-1298
运用含氢键缔合的格子流体状态方程(LFHB), 仅用一个参数关联了一元醇-惰性溶剂共17个体系29套1H NMR化学位移数据. 并且用关联参数成功预测了不同温度下丁醇+环己烷的化学位移. 所得结果与化学缔合理论的结果进行了比较. 对于某些体系在稀浓度范围LFHB的计算氢键缔合度要低于化学缔合理论的结果. 并且分析了LFHB理论中的物理参数和化学参数对于缔合度计算的不同影响.  相似文献   

12.
A solvent‐free synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones from aromatic aldehydes, β‐keto ester/acetyl acetone and urea catalysed by cupric acetate under thermal condition is reported as a simple and an efficient protocol. Compared with classical Biginelli reaction reported in 1893, this new method provides much improved modification in terms of yield and reaction time. The usage of milder catalyst, environmental friendly procedures and excellent yields within a very short time (5–15 min) are the advantages of the method in which the involvement of solvent‐free condition adds an edge to the method. Thus, the efficiency of the protocol enabled the rapid synthesis of 3,4dihydropyrimidin‐2(1H)‐one derivatives in a short duration.  相似文献   

13.

Free‐radical homopolymerization and copolymerization of phenacyl methacrylate (PAMA) with methyl methacrylate (MMA) was done using 2,2′‐azobis(isobutyronitrile) (AIBN) as the initiator in 1,4‐dioxane at 60°C. 1H‐NMR and FT‐IR spectroscopy confirmed the existence of OCH2 and CH signals and unsaturated structure and CN stretch at the chain end of low molecular weight poly(phenacyl methacrylate)[poly(PAMA)], respectively. The six‐membered ring with both ester and ether at the end group was detected by 1H‐NMR. In the poly(PAMA), the end groups formed due to chain transfer reactions were found in large concentrations. The mechanism of the formation of end groups has been presented. The behavior of free radical polymerization of PAMA was compared with that of phenoxycarbonylmethyl methacrylate (PCMMA). The molecular weight distribution of the homo and copolymers was determined using gel permeation chromatography. Thermal properties of the polymers were determined using differential thermal analysis (DTA) and thermogravimetric analysis (TGA).  相似文献   

14.

Free‐radical homopolymerization and copolymerization of phenacyl methacrylate (PAMA) with methyl methacrylate (MMA) was done using 2,2′‐azobis(isobutyronitrile) (AIBN) as the initiator in 1,4‐dioxane at 60°C. 1H‐NMR and FT‐IR spectroscopy confirmed the existence of OCH2 and CH signals and unsaturated structure and CN stretch at the chain end of low molecular weight poly(phenacyl methacrylate) [poly(PAMA)], respectively. The six‐membered ring with both ester and ether at the end group was detected by 1H‐NMR. In the poly(PAMA), the end groups formed due to chain transfer reactions were found in large concentrations. The mechanism of the formation of end groups has been presented. The behavior of free radical polymerization of PAMA was compared with that of phenoxycarbonylmethyl methacrylate (PCMMA). The molecular weight distribution of the homo and copolymers was determined using gel permeation chromatography. Thermal properties of the polymers were determined using differential thermal analysis (DTA) and thermogravimetric analysis (TGA).  相似文献   

15.
韩大雄  杨频 《化学学报》2005,63(15):1409-1414
为了合理化设计、指导具有高活性、低毒性的石杉碱甲杂合体(Huprine X)衍生物的合成, 建立了一个计算结合自由能的新方案, 以实现对该类衍生物活性排列顺序的预测. 该结合自由能由三部分组成: 抑制剂和靶酶的相互作用能; 活性位点残基在结合前后的构象绝对自由能的变化; 抑制剂从稳定构象变为活性构象的自由能增加值. 通过计算已合成的14个杂合体衍生物的结合自由能, 结果显示理论值和实验测定的生物活性值有很好的等级相关性, 其斯皮尔曼相关系数为0.85, 证明了该方法的可行性.  相似文献   

16.
Earlier the intramolecular inversion of the 18-crown-6 molecules was found in the complex ion pairs [Ln(ptfa)2 (18-crown-6)]+ [Ln(ptfa)4] (H2O)4 where Ln = La(1), Ce (2), Pr (3), Nd (4), and ptfa is 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione. In this work the peculiarities of the molecular structure and dynamics were studied for [Eu(ptfa)2 (18-crown-6)]+ [Eu(ptfa)4] (H2O)4 (5) by NMR spectroscopy techniques. Through VT-NMR spectra analysis the temperature dependence was obtained for the rate constant. The free energy ΔG(320) of 18-crown-6 ring inversion activation was found to be 65 ± 5 kJ mol−1 for 5 in CDCl3. This result is comparable with the earlier data [S.P. Babailov and D.A. Mainichev: J. Inclusion Phenom. Macrocyclic Chem. 43, 187–193 (2002)] for complexes 2, 3, 4 in deuterated toluene (ΔG(320)=65 ± 9, 64 ± 9, 64 ± 9 kJ mol−1 respectively). It was found by relaxation NMR spectroscopy that the effective distance between Ln and protons of the crown molecule is 4.5 ± 0.2 Å. The analysis of structural parameters testifies that the crown ether and chelated anions are in the first coordination sphere of a Ln cation. Obtained geometrical parameters show that the complex cations of Eu, Ce and Pr have similar spatial structures.This revised version was published online in July 2005 with a corrected issue number.  相似文献   

17.
Homogeneous catalysts for the water gas shift reaction prepared from Rh2(-Pz)2(COD)2 (Pz = pyrazolate ion and COD = 1,5-cyclooctadiene) in aqueous organic solvent media (pyridine, 4-picoline or 2-ethoxyethanol) and Rh2(-Pz)2(CO)2(TPPMS)2 (TPPMS = meta-sulfonatophenyl-diphenyldiphosphine) in acidic aqueous media under mild conditions are described. In situ FT-IR, 1H and 13C NMR spectroscopic studies of the Rh2(-Pz)2(COD)2 catalytic system reveal the presence of hydrido-Rh complexes with linear and bridging carbonyls. These complexes also catalyze the reduction of nitrobenzene to aniline.  相似文献   

18.
The longitudinal relaxation times (T1)of 1H NMR signals for a variety of alkanols in D2Omarkedly decreased with increasing concentrations (c)of - and -cyclodextrins (CD). Tetramethylammoniumchloride (TMA) used as an internal reference wasavailable for evaluating an effect of solutionviscosity on relaxation rates R(=1/T1), since TMAshowed no appreciable interaction with CD. Changes inthe ratio of R for alkanol protons to R for TMAprotons with c were analyzed by the curve-fittingmethod to give Ka. These Ka values agreedwell with those obtained by the analysis of changesin , indicating that T1 measurement is available forthe determination of Ka for CD complexes. 2D ROESYspectra provided definite information on the molecularstructures of CD complexes with alkanols.  相似文献   

19.
对于碳-氧双键和亲核试剂的加成反应,由于负离子进攻为反应速度决定步骤,人们普遍认为羰基的反应性能主要取决于碳原子上的正电荷量,正电荷愈多亲核试剂愈易加成,全部反应也愈易进行。并认为酮的羰基的亲电能力比醛弱,这是由于酮的羰基和2个烃基相结合,如为烷基,具有给电子作用,则增加羰基碳原子电负性,降低其亲电能力。  相似文献   

20.
粒度对纳米体系化学反应热力学性质的影响   总被引:5,自引:0,他引:5  
为了研究纳米粒子的粒度对化学反应热力学性质的影响规律, 以球形原子簇来模拟纳米金刚石颗粒, 用量子化学方法对粒度不同的金刚石纳米粒子与氧气反应的热力学性质进行了计算. 结果表明, 粒度对多相反应的标准摩尔反应焓△rH0m、标准摩尔反应熵△rS0m、标准摩尔反应吉布斯函数△rG0m和标准平衡常数K0均有明显的影响, 随着反应物粒径的减小, △rH0m、△rS0m和△rG0m均降低,而K0增大. 这些影响规律与实验结果基本一致.  相似文献   

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