稀土硝酸盐与穴醚(2.2)及穴醚(2.2.2)配合物的合成和性质

由三价稀土、镧、铕和镱的硝酸盐分别与穴醚(2.2),穴醚(2.2.2)反应,合成相应的五种固体配合物,并进行了元素分析,IR,NMR,TG,DTA,电化学等性质的研究。     

稀土—色氨酸配合物的pH电位法研究

稀土－色氨酸配合物的ｐＨ电位法研究朱元成（甘肃省天水师范高等专科学校化学系天水７４１００１）邓汝温（兰州大学化学系兰州７３００００）朱春吉倪嘉缵（长春应用化学研究所稀土化学与物理开放实验室长春１３００２２）关键词稀土色氨酸配合物ｐＨ电位法中图分类号Ｏ...     

非水溶剂中稀土离子和穴醚（2.2）配合物的电导研究

用电导法研究了２５℃时，硝酸稀土和穴醚在不同溶剂中的配位行为。计算了１：１配合物的稳定常数及摩尔电导率，在非水溶剂（ＣＨ３）２ＣＯ．ＣＨ３ＣＮ．ＣＨ３ＯＨ和ＤＭＦ中，由于配位过程中伴随着Ｌｎ离子的溶剂化作用，稀土和穴醚配合的稳定常数随Ｌｎ原子序数的增加而变化不大。     

二（2，6－二叔丁基－4－甲基苯氧基）钐配合物催化甲基丙烯酸甲酯聚合

二（２，６－二叔丁基－４－甲基苯氧基）钐配合物催化甲基丙烯酸甲酯聚合扈晶余，齐贵中（中国科学院长春应用化学研究所稀土化学与物理开放实验室长春１３００２２）沈琪（苏州大学化学系苏州）关键词钐配合物，甲基丙烯酸甲酯，聚合二价稀土有机化合物具有很强的还原性...     

拉曼光谱研究稀土离子及其配合物对DPPE双分子层脂链结构的影响

拉曼光谱研究稀土离子及其配合物对ＤＰＰＥ双分子层脂链结构的影响赵冰（吉林大学分子光谱与分子结构开放实验室长春１３００２３）袁春波，赵大庆，倪嘉缵（中国科学院应用化学研究所稀土化学与物理开放实验室长春１３００２２）随着稀土在工农业和医疗保健上的广泛应用...     

二（叔丁基环戊二烯基）钕甲基配合物催化丙烯腈聚合

二（叔丁基环戊二烯基）钕甲基配合物催化丙烯腈聚合任劲松，扈晶余，沈琪（中国科学院长春应用化学研究所稀土化学与物理开放实验室长春１３００２２）（苏州大学化学系苏州）关键词丙烯腈，配位聚合，钕配合物丙烯腈聚合通常采用ＢＦ＿３、ＴｉＣｌ＿４、过氧化苯甲酰￣...     

二价芳氧钐配合物催化苯乙烯聚合

二价芳氧钐配合物催化苯乙烯聚合齐贵中扈晶余＊沈琪（中国科学院长春应用化学研究所稀土化学与物理开放实验室长春１３００２２）（苏州大学化学系苏州）关键词钐配合物，苯乙烯，聚合１９９６－０５－１８收稿，１９９６－１０－３０修回国家科委攀登计划及国家自然科学...     

生理条件下铽、钙离子与氨基酸配位作用的研究

生理条件下铽、钙离子与氨基酸配位作用的研究赵淑富,王增林,刘启民,牛春吉,倪嘉缵（中国科学院长春应用化学研究所稀土化学与物理开放实验室,长春,１３００２２）关键词铽,钙,氨基酸配合物钙是主要的生命必需元素,它具有多种重要生物功能。进入体内的稀土离子可...     

稀土与穴醚[2,1,1]配位反应过程中的阴离子重排现象

用电导法研究了甲醇溶液中稀土硝酸盐及氯化物与穴醚［２，１，１］的配位作用，测定了１：１配合物的稳定常数ｌｇＫ及摩尔电导ΛＭＬ。在甲醇溶液中，稀土氯化物与［２，１，１］配合物的稳定性大于硝酸盐的相应配合物。稀土硝酸盐与［２，１，１］配合物的稳定常数ｌｇＫ随镧系收缩有明显的钆断效应。电导测定表明，在甲醇溶液中，稀土硝酸盐为弱电解质。轻稀土与［２，１，１］反应后为１：１型电解质，重稀土配合物则属１：２型电解质；稀土氯化物在甲醇中为１：１型电解质，所形成的配合物均为１：２型电解质。     

若干多氮双核银(Ⅰ)大环化合物的合成和电化学

本文在硝酸银存在下,用二乙撑三胺、三（2－氨基乙基）胺分别和以间苯二醛为母体的二醛缩合,得到了系列双核银（Ⅰ）和多氮环合物和穴合物。对所得产物进行了表征,并利用循环伏安法对配合物的电化学进行了研究。探讨了环空腔大小及取代基不同对配合物中银（Ⅰ）电化学行为的影响。     

Hydrogen bonding patterns in the cocrystals of 5-nitrouracil with several donor and acceptor molecules

: Cocrystals of 5-nitrouracil with solvent molecules, dioxane, pyridine, DMSO, formamide and ethanol as well as with piperazine, N, N'-dimethylpiperazine, 3-aminopyridine and diazabicyclo [2.2.2]octane obtained by deliberate inclusion, have been examined by X-ray crystallography. The tape structure found in the parent centric form of nitrouracil is retained with some modifications in the cocrystals with dioxane, piperazine, diazabicyclo [2.2.2]octane, N,N'-dimethylpiperazine, pyridine and DMSO, with the guest molecules forming alternate tapes. In cocrystals involving formamide, ethanol and 3-aminopyridine, the molecular tapes exhibit mixed compositions. The observed bonding patterns have been classified into six schemes. Interestingly, quadruple type hydrogen bonding patterns are seen in cocrystals containing 3-aminopyridine or ethanol and water, while a network of acyclic tetrahedral pentamers of water is found in the cocrystal containing diazabicyclo [2.2.2]octane and water.     

硝酸铕和穴醚配合物的电化学研究

用循环伏安法在二氯甲烷、二氯乙烷、乙腈、丙酮,苯腈、吡啶、二甲基甲酰胺、二甲基亚砜等不同溶剂中,研究了稀土穴醚配合物Eu(NO₃)₃(2,2)和Eu₂(NO₃)₆(2,2,2)的电化学行为。测定了其氧化还原反应的半波电位及电子转移速度常数,讨论了E_1/2、k_s与溶剂及支持电解质的关系。     

[Eu2(TCM)2(DMSO)6]·2DMSO双核笼状稀土配合物的合成与结构

报道一个H3TCM配体在较小尺寸的溶剂DMSO中与稀土离子Eu3+通过自组装形成的双核笼状结构, 从中可进一步看出溶剂分子的尺寸对该双核结构的影响.     

萘甲酸功能化聚砜的制备及其与Eu(Ⅲ)稀土离子配合物的荧光发射特性

以1,4-二氯甲氧基丁烷(BCMB)为氯甲基化试剂,使聚砜(PSF)氯甲基化(CM),形成氯甲基化聚砜(CMPSF),然后用6-羟基-2-萘甲酸(HNA)使CMPSF的氯甲基与HNA的酚羟基之间发生亲核取代反应,将萘甲酸(NA)配基键合在聚砜侧链,制得了功能化改性的聚砜NAPSF。采用红外光谱和核磁共振氢谱对其结构进行了表征。考察了主要因素对CMPSF与HNA之间亲核取代反应的影响规律,分析了反应机理,优化了反应条件。结果表明,CMPSF与HNA之间取代反应的速率与亲核试剂HNA的浓度无关,遵循SN1的反应机理;使用极性较强的溶剂二甲亚砜,有利于亲核取代反应的进行;在适宜条件下,CMPSF的氯甲基转化率可达96%,NA的键合量为1.68 mmol/g。将NAPSF与Eu(Ⅲ)离子配位,制得了聚合物-稀土配合物NAPSF-Eu(Ⅲ),它不仅发射出Eu3+离子的特征荧光,而且对Eu3+离子的荧光发射显示出很强的敏化作用。萘甲酸功能化的大分子配基NAPSF对Eu3+离子的敏化作用,远强于苯甲酸(BA)功能化的大分子配基BAPSF对Eu3+离子的敏化作用。     

Stability of Ag Cryptate in Mixed Solvent with Negative Deviations from Additivity

Coordination model of solvation was used to analyze the change in stability constants of Ag(I) cryptate in water–DMSO solvent. The resolvation constants, distribution of solvatocomplexes, and composition of solvation shells of Ag⁺ and 2.2.2-cryptand in a mixed solvent were determined and the effect of solvation of coordinating (reaction) centers of reagents on the stability of a complex was estimated. It was shown that specific intermolecular interactions of water and organic component of a mixed solvent should be taken into consideration when studying the equilibria of complexation in such systems.     

Studies in the heterocyclic series. XI. Reactions of 2-Amino-3-hydroxypyridine with 2-Chloro-3-nitropyridine

The reactions of 2-amino-3-hydroxypyridine and 2-chloro-3-nitropyridine in various solvents and in the presence of certain catalysts were studied. A dilute acid-catalysed procedure led to a 45% yield of 3-hydroxy-3-nitro-2,2-dipyridylamine which was also obtained by refluxing in alcoholic potassium hydroxide for several hours. The diarylamine was converted to 1,9-diazaphenoxazine by base-catalysed intramolecular condensation in refluxing DMSO. The same diazaphenoxazine was obtained directly by prolonged base-catalysed reaction of the starting pyridine compounds in DMSO. From a study of the infrared spectrum of the diarylamine precursor, it was found that strong NHO hydrogen bonding is responsible for the failure of the cyclization step in either aqueous or alcoholic base. This problem was overcome by the use of DMSO as the reaction solvent. Structural assignments were made by a study of their ultraviolet, infrared, nmr and mass spectra and the mechanistic pathways were also discussed.     

Theoretical study on electronic and spin structures of [Fe2S2](2+,+) cluster: reference interaction site model self-consistent field (RISM-SCF) and multireference second-order Møller-Plesset perturbation theory (MRMP) approach

Electronic structures of [Fe(2)S(2)(SCH(3))(4)](2-,3-) in DMSO solution are calculated using reference interaction site model complete active space self-consistent field (RISM-CASSCF)/multireference second-order M?ller-Plesset perturbation theory (MRMP) method. For the reduced state, we obtain both the low-spin Fe(3+)Fe(2+) localized and high-spin Fe(2.5+)Fe(2.5+) delocalized forms, which are very close in energy. The spin interaction constants obtained from the energies of states with various spin multiplicities are in good agreement with the available experimental estimates both for the oxidized and for the reduced states. The dynamic electron correlation effect is found to be important in estimating the spin interaction between the Fe ions. The redox potentials are calculated to be 2.87 and 2.78 eV for the localized and delocalized reduced states, respectively, which are close to the experimental values. We devise a simple model for calculating the free energy curves of the reduction process based on the RISM-SCF theory. The activation barrier height is calculated to be 7.4 kcal/mol at the equilibrium geometry of oxidized state, indicating that the reduction reaction will occur efficiently in DMSO solvent. The effect of solvent fluctuation on the free energy profiles is discussed on the basis of the present calculations.     

Solvation controlling reaction paths and gel-formation in imide derivatives

1,8-Naphthalic anhydride condenses with 4-nitro-1,2-diaminobenzene in acetic acid to give 11-nitrobenzo[d,e]benzo[2,1-a]isoquinoline-1,3-dione (1), whereas the same reaction carried out in DMF gives 2-(2-amino-4-nitrophenyl)-benzo[d,e]isoquinoline-1,3-dione (2). The condensation reaction of 1,8-naphthalic anhydride with 1-amino 3,5-benzene dicarboxylic acid leads to corresponding imide, which forms a gel in a mixed solvent such as water in DMSO. A similar compound 5-(1,3-dioxo-1,3-dihydroisoindol-2-yl)-isophthalic acid derived from phthalic anhydride forms gel in a mixed solvent of DMSO and water, whereas a crystalline solvate of DMSO with 2 could be obtained upon crystallization from DMSO. The crystal structure of this solvate is determined and its structure is compared with 2-(1,3-dioxo-1,3-dihydro-isoindol-2-yl)-benzoic acid. The latter does not form a gel in the mixed solvent and adopts an intermolecular hydrogen bonded structure.     

Microsolvation of DMSO: Density functional study on the structure and polaraizabilities

The structure and stability for the association of water with dimethyl sulfoxide (DMSO) are investigated using the density functional M06‐2X level theory. Stable complexes are formed by the formation of hydrogen bonding between water and oxygen atom of DMSO molecule, while the electrostatic force between water and DMSO plays a vital role in deciding the structure. The water‐DMSO interactions are stronger than the interwater hydrogen bonds, which can be inferred from the shorter DMSO‐water bond distance compared with the water–water bond distance. The calculated solvent association energy does not saturate, and it remains favorable to attach additional water molecules to the existing water network. The calculated IR spectra shifts supports the formation stronger hydrogen bonding, while the electrostatic potential (ESP) plot supports the existence of weaker electrostatic interaction in the studied clusters. The polarizabilities for the ground state clusters were found to increase monotonically with the cluster size. The presence of additional electrostatic bonding between water and DMSO, devastates the linear hydrogen‐bonding network. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011