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681.
稀土配合物RE(TPTZ)Cl_3的合成、表征及荧光性能研究 总被引:1,自引:0,他引:1
首次以2,4,6-三吡啶基三嗪(TPTZ)与Sm, Eu, Tb和Dy氯化物反应,合成四种单一稀土配合物以及Tb分别1∶1掺Gd, Y, La的三种异核配合物。经元素分析、稀土络合滴定、摩尔电导率、红外光谱、紫外光谱和差热-热重测定表明,配合物的组成分别为RE(TPTZ)Cl3·3H2O(RE=Sm, Eu, Tb, Dy)和Tb0.5Ln0.5(TPTZ)Cl3·3H2O(Ln=Gd, Y, La);TPTZ作为三齿配体与稀土离子配位,即中心环提供一个N原子,两个吡啶环分别提供一个N原子;配合物中3个水分子与稀土离子配位,1个Cl-在外界,2个在内界,为1∶1型电解质;配合物内外界可能为[RE(TPTZ)(H2O)3Cl2] Cl,稀土离子的配位数为8。配合物的荧光光谱测试表明,四种单一稀土配合物中,Tb配合物发光最强;三种1∶1掺杂异核Tb配合物荧光强度大于纯Tb配合物,表明Y3+, La3+和Gd3+都可以敏化Tb3+的发光,其中Gd3+的敏化作用最强,Y3+次之,La3+最差。 相似文献
682.
《Tetrahedron》2019,75(40):130571
An efficient asymmetric [3 + 2]-cycloaddition reaction of 3-isothiocyanato oxindoles and formaldimines in-situ generated from 1,3,5-trisubstituted-hexahydro-1,3,5-triazines with a cinchona alkaloid-derived thiourea as the catalyst has been developed. A range of biologically important spiro-imidazolidinethione-oxindoles were obtained in excellent yields with good enantioselectivities (up to 99% yield and 93% ee). 相似文献
683.
The bromo‐substituted aromatic dicarboxylic acid 5‐amino‐2,4,6‐tribromoisophthalic acid (H2ATBIP), in the presence of the N‐donor flexible bipyridyl‐type ligands 1,3‐bis(pyridin‐4‐yl)propane (bpp) and N,N′‐bis(pyridin‐4‐ylmethyl)oxalamide (4‐bpme) and ZnII ions, was used as an O‐donor ligand to assemble two novel luminescent metal–organic frameworks (MOFs), namely poly[[(μ‐5‐amino‐2,4,6‐tribromoisophthalato‐κ2O1:O3)[μ‐1,3‐bis(pyridin‐4‐yl)propane‐κ2N:N′]zinc(II)] dimethylformamide monosolvate], {[Zn(C8H2Br3NO4)(C13H14N2)]·C3H7NO}n, ( 1 ), and poly[[(μ‐5‐amino‐2,4,6‐tribromoisophthalato‐κ2O1:O3)diaqua[μ‐N,N′‐bis(pyridin‐4‐ylmethyl)oxalamide‐κ2N:N′]zinc(II)] monohydrate], {[Zn(C8H2Br3NO4)(C14H14N4O2)(H2O)2]·H2O}n, ( 2 ), using the solution evaporation method. Both ( 1 ) and ( 2 ) were characterized by FT–IR spectroscopy, elemental analysis (EA), solid‐state diffuse‐reflectance UV–Vis spectroscopy, and powder and single‐crystal X‐ray diffraction analysis. Complex ( 1 ) shows a two‐dimensional (2D) corrugated layer simplified as a 2D (4,4) topological network. The supramolecular interactions (π–π stacking, hydrogen bonding and C—Br…Br halogen bonding) play significant roles in the formation of an extended three‐dimensional (3D) supramolecular network of ( 1 ). Complex ( 2 ) crystallizes in the chiral space group P212121 and exhibits a novel 3D homochiral framework, showing a diamond‐like topology with Schläfli symbol 66. The homochirality of ( 2 ) is further confirmed by the solid‐state circular dichroism (CD) spectrum. The second harmonic generation (SHG) property of ( 2 ) was also investigated. The hydrogen and C—Br…Br/O halogen bonding further stabilize the framework of ( 2 ). The central ZnII ions in ( 1 ) and ( 2 ) show tetrahedral and octahedral coordination geometries, respectively. The coordinated and uncoordinated water molecules in ( 2 ) could be removed selectively upon heating. Most importantly, ( 1 ) and ( 2 ) show rapid and highly sensitive sensing for a large pool of nitroaromatic explosives (NAEs). 相似文献
684.
Ya-Qian Zhang Vladislav A. Blatov Xiu-Xiu Lv Ding-Yi Tang Lin-Lu Qian Ke Li Bao-Long Li 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(7):960-968
Coordination polymers (CPs) have been widely studied because of their diverse and adjustable topologies and wide‐ranging applications in luminescence, chemical sensors, magnetism, photocatalysis, gas adsorption and separation. In the present work, two coordination polymers, namely poly[(μ5‐benzene‐1,3,5‐tricarboxylato‐κ6O1:O1′:O3:O3:O5,O5′){μ3‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ3N:N′:N′′}di‐μ3‐hydroxido‐dicobalt(II)], [Co2(C9H3O6)(OH)(C12H12N6)]n or [Co2(btc)(OH)(mtrb)]n, (1), and poly[[diaquabis(μ3‐benzene‐1,3,5‐tricarboxylato‐κ3O1:O3:O5)bis{μ3‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ3N:N′:N′′}tetra‐μ3‐hydroxido‐tetracopper(II)] monohydrate], {[Cu4(C9H3O6)2(OH)2(C12H12N6)2(H2O)2]·H2O}n or {[Cu4(btc)2(OH)2(mtrb)2(H2O)2]·H2O}n, (2), were synthesized by the hydrothermal method using 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene (mtrb) and benzene‐1,3,5‐tricarboxylate (btc3?). CP (1) exhibits a (3,8)‐coordinated three‐dimensional (3D) network of the 3,8T38 topological type, with a point symbol of {4,5,6}2{42·56·616·72·82}, based on the tetranuclear hydroxide cobalt(II) cluster [Co4(μ3‐OH)2]. CP (2) shows a (3,8)‐coordinated tfz‐d topology, with a point symbol of {43}2{46·618·84}, based on the tetranuclear hydroxide copper(II) cluster [Cu4(μ3‐OH)2]. The different (3,8)‐coordinated 3D networks based on tetranuclear hydroxide–metal clusters of (1) and (2) are controlled by the different central metal ions [CoII for (1) and CuII for (2)]. The thermal stabilities and solid‐state optical diffuse‐reflection spectra were measured. The energy band gaps (Eg) obtained for (1) and (2) were 2.72 and 2.29 eV, respectively. CPs (1) and (2) exhibit good photocatalytic degradation of the organic dyes methylene blue (MB) and rhodamine B (RhB) under visible‐light irradiation. 相似文献
685.
本文通过Suzuki偶联反应高效合成了两种三萘基三嗪化合物,即2,4,6-三(1-萘基)-1,3,5-三嗪(T1NT)和2,4,6-三(2-萘基)-1,3,5-三嗪(T2NT). 考察了介质的极性、温度以及THF-H2O二元溶剂体系中的溶解性等因素对它们吸收和发射光谱行为的影响.研究发现, 由于T1NT比T2NT具有更好的分子平面性,其激发态下分子内电荷转移的程度较大,导致其在溶液中吸收光谱、发射光谱比T2NT呈现显著红移.冻结态下,分子平面性较差的T2NT显示出较短波长的发光. 相似文献
686.
HUANG Qiang FU Qiangqiang LIU Yajing BAI Jinying WANG Qianying LIAO Huimin GONG Ping 《高等学校化学研究》2014,30(2):257-265
In an attempt to develop potent and selective anticancer agents,we designed and synthesized a series of novel bis(morpholino-1,3,5-triazine) derivatives beating aylmethylene hydrazine moiety and evaluated their cytotoxicity,in vitro,against H460(non-small-cell lung cancer),HT-29(human colorectal cancer) and MDA-MB-231(human breast cancer) cell lines.The pharmacological results indicate that all the compounds exhibit enhanced cytotoxicity than BMCL-200908069-1,and six target compounds(7e,7h,7j,9a,9b,9c) were superior to PAC-1 against all the tested cancer cell lines.The most active compound 7j,with IC50(inhibitory concentration 50%)values of 0.75,0.34 and 0.60 μ mol/L against HT-29,H460 and MDA-MB-231 cancer cell lines,was 39-,28-,and 60-fold more potent than BMCL-200908069-1 (29.24,9.52 and 36.21 μmol/L),respectively. 相似文献
687.
以2,4-二氯-6-辛氧基-1,3,5-三嗪为原料,经Kumada偶联及胺化两步反应合成了三嗪胺衍生物:4-(9-蒽基)-6-辛氧基-1,3,5-三嗪-2-胺(AOOTA),总产率为38%.通过紫外-可见吸收光谱及荧光光谱研究了氯仿溶液中AOOTA在乙酸(HOAc)及三氟乙酸(TFA)作用下的光谱行为.研究发现AOOTA与HOAc在基态及激发态下均不能发生双氢键作用,而AOOTA与TFA相互作用基态下形成双氢键复合物,激发态下由于分子中蒽基及辛氧基与三嗪环间的C-C单键以及C-O单键的自由旋转,从而使得AOOTA与TFA分子间不能形成有效的氢键相互作用. 相似文献
688.
反相气相色谱法研究1,3,5-三氨基-2,4,6-三硝基苯的表面特性 总被引:2,自引:0,他引:2
采用反相气相色谱技术(IGC)研究了4种不同粒度的1,3,5-三氨基-2,4,6-三硝基苯(TATB)的表面性质。4种不同粒度的TATB表面自由能的色散分量(γds)随着温度的升高而增加;粒度越大的粒子,其色散自由能上升越快;在较高温度下,粗颗粒TATB显示了更强的色散作用(γds=193.2 mJ/m2,353 K),粒度最小的亚微米TATB显示了最弱的色散作用(γds=64.0 mJ/m2,353 K)。由于制备方法不同和粒子大小的差异,4种TATB的表面酸碱性质显示了明显的差别,细颗粒TATB表面有较强的亲电子特性;而其他3种TATB在极性探针分子的作用下的吸附均表现为吸热吸附,表现出在分子内和分子间具有强烈的相互作用,其Ka和Kb值均为负。 相似文献
689.
TATB基PBX结合能和力学性能的理论研究 总被引:11,自引:1,他引:10
以SCF-MO-AM1方法和MM-COMPASS力场, 对TATB (1,3,5-三氨基-2,4,6-三硝基苯)与系列高聚物组成的PBX(高聚物粘结炸药)尺寸匹配原子簇, 分别进行全优化几何构型计算, 发现两种方法求得的结合能存在良好的线性关系. 对TATB (3×3×4)超晶胞及其与系列氟聚物组成的双组分PBX, 实施COMPASS力场下的分子动力学(MD)周期性模拟计算, 首次求得其弹性系数、模量和泊松比, 发现添加少量高聚物即能有效改善炸药的力学性能. 相似文献
690.
Takakazu Yamamoto Shoutaro Watanabe Hiroki Fukumoto Masaru Sato Tsuyoshi Tanaka 《Macromolecular rapid communications》2006,27(5):317-321
Summary: Alternating copolymers between substituted 1,3,5‐triazine (substituent = alkyl or amine) and thiophene or bithiophene are synthesized. The copolymer of amino‐1,3,5‐triazine with thiophene is soluble in organic solvents, transparent in most parts of the visible region, and photoluminescent. The copolymer receives electrochemical n‐doping with an Epc of −2.08 V vs Ag+/Ag and shows a time‐of‐flight electron drift mobility of 2.0 × 10−4 cm2 · V−1 · s−1, which is larger than that of widely used Al(8‐quinolinolato)3.