稀土苯二甲酸配合物的发光性能和分子内能量传递(英文)

合成和表征了一系列稀土（钆，铕，铽）的邻（间）苯二甲酸配合物．通过测定了苯二甲酸配体的钆配合物的低温磷光光谱确定其相应苯二甲酸配体的最低三重态能级．同时详细讨论了配合物的发光性能，能级匹配和分子内能量传递机制．     

吡啶二甲酸类配体-EDTA-铽三元配合物的荧光性能

对几种吡啶－２,６－二甲酸类配体与ＥＤＴＡ、铽的三元配合物在溶液中的荧光性能进行了研究,溶液ＰＨ值和溶剂效应对体系荧光的影响也分别进行了探讨。４－甲氧基吡啶－２,６－二甲酸和４－乙氧基吡啶－２,６－二甲酸等配体在这种三元体系中的敏化性能比常用的吡啶－２,６－二甲酸好,其中４－乙酰氨基吡啶－２,６－二甲酸特别优异。不论在二元配合物系还是在三元配合物体系中,均具有发光强度大、寿命长的特点。     

具有双光子效应的多核配合物

双光子吸收材料在上转换发光、生物成像、光动力学治疗、三维微结构加工等领域有着广泛的应用。金属配合物可通过金属中心为模板将数个具有双光子活性的有机配体组合成为复杂的多极体系从而增强双光子效应,还能使所得的双光子吸收材料的稳定性、发光寿命以及光谱的可调性得以优化,其中多核金属配合物的双光子吸收截面表现出的“协同增强”效应更是引起广泛关注。本文选取典型的多核配合物（分为同多核和异多核）,重点总结金属离子的种类和数量、配体分子以及配合物的结构等参数对其双光子性能的影响,特别关注多核配合物激发态的结构和能级、能量传递的模式和方向等对其光物理性质的影响机制,希望总结具有双光子活性的多核配合物的分子设计规律。最后,对目前具有双光子活性的多核配合物的制备以及“多核双功能”型配合物的开发研究方面存在的问题进行阐述和展望,以期为新型双光子吸收材料的构筑提供参考。     

铽-芳香羧酸-丙烯腈三元配合物的合成及发光性能

铽-芳香羧酸-丙烯腈三元配合物的合成及发光性能;铽;芳香羧酸;丙烯腈;三元配合物;发光性能     

高氯酸铕、铽-二苯亚砜-1，10菲咯啉配合物的合成及荧光性质研究

同时合成了高氯酸铕、铽.二苯亚砜-1,10菲咯啉三元配合物和高氯酸铕、铽-1,10菲咯啉二元配合物。以配合物进行了元素分析,摩尔电导。确定了配合物的组成分别为:[RE(DPSO)](phen)3(ClO4)2)ClO4·nH2O(n=1,3,DPSO为二苯亚砜,phen为1,10菲咯啉)和RE(phen)4(ClO4)3。红外光谱研究表明:DP-SO以氧原子与稀土离子配位;phen以氮原子与稀土离子配位;三元配合物中ClO4-中两个与稀土离子配位,二元配合物中三个ClO4-均与稀土离子配位。对比研究了两类配合物的发光性能,溶解性能及稳定性能。研究结果表明:第二配体DPSO的加入,大大改善了配合物的发光性能,可分别使铕、铽的发光强度提高2和8倍。同时大大改善了配合物的溶解性能及稳定性能。     

活性铽三元荧光配合物的合成、表征及性能研究

本文以对甲基苯甲酸、对氨基苯甲酸、磺基水杨酸、大茴香酸、间氯苯甲酸为第一配体,丙烯腈为活性配体,合成了五种新的铽芳香羧酸丙烯腈三元配合物。通过元素分析,EDTA配位滴定分析,热分析,红外、紫外、荧光光谱分析对目标配合物的组成、结构进行了表征,并研究了它们的发光性能。结果表明,五种新的活性铽三元配合物均具有良好的发光性能,各芳香羧酸向铽离子传递光能的动力为:大茴香酸>对甲基苯甲酸>间氯苯甲酸>磺基水杨酸>对氨基苯甲酸,将这些含活性配体丙烯腈的发光铽配合物引入高分子化合物中可望合成出键合型铽高分子发光材料。     

稀土铕、铽配合物在温度发光传感领域的研究进展

稀土发光配合物材料基于其独特的4f-4f电子跃迁表现出优异的发光性能,特别是铕和铽配合物材料,发光波长在可见光区范围内,发射谱带狭窄且尖锐(半峰宽通常小于10 nm),非常适合应用于显示设备和传感装置。同时,具备温度依赖发光性能的铕和铽配合物能够实现高灵敏度、高效的温度传感过程,使其有望用于流体动力学、航空航天、环境工程、能源技术等领域温度的测量和监控。本综述详细介绍了近10年来,铕和铽配合物温度传感体系的研究进展,总结了配合物材料类别以及温度响应灵敏度影响因素,进一步归纳了振动弛豫、能量转移等几类响应机制,并详细介绍了铕/铽发光配合物光学比率温度计的研究成果,为镧系金属配合物温度传感性能的研究进行了全面总结,以期打开此类材料实际应用的大门。     

邻苯二甲酸铽配合物与铕离子间能量传递

本文应用红外光谱、紫外吸收光谱、稳态和时间分辨荧光光谱研究了邻苯二甲酸铽及邻甲基苯甲酸铽配合物的发光性能,配位体结构以及铕离子对配合物发光的猝灭方式,并探讨了溶剂、pH值对发光强度和寿命的影响。     

2-烯丙基-1,3-二苯基-1,3-丙二酮的合成及其稀土配合物光致发光性质研究

用相转移催化法合成了2－烯丙基－1，3－丙二酮（ADBM）及其稀土配合物，用元素分析，IR和1HNMR对化合物进行了表征，研究了烯丙基的引入对稀土配合物发光性能的影响。结果表明：烯丙基的引入降低了二苯甲酰甲烷（DBM）对Eu^3 的敏化作用，发光减弱，增强了二苯甲酰甲烷对Tb^3 的敏化作用，发光增强：ADBM是铽的优良配体，是电子效应，能量匹配原理对此现象进行了解释。     

对—苯二甲酸邻菲罗啉铕镧配合物的红外光谱及荧光光谱研究

用对-苯二甲酸铵和邻菲罗啉与氯化铕和氯化镧在乙醇-水溶液中反应,合成了对-苯二甲酸邻菲罗啉铕镧异核稀土配合物,测定了配合物的C,H,N和稀土元素的含量、红外光谱、紫外光谱及荧光光谱,确定了配合物的组成。结果表明,羧基氧和邻菲罗啉氮原子均与稀土离子配位,桥联配体对-苯二甲酸根可有效的传送能量,不发光的镧离子对铕离子的发光有明显的增强作用。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.