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对两种带有不同取代基吡唑啉化合物的光谱和光物理行为进行了比较研究.结果表明,吡唑啉环3-位处所联基团推一拉电子能力的改变对化合物的荧光量子产率、荧光猝灭等有巨大影响.这是由吡唑啉化合物本身的结构特征所决定的. 相似文献
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含"单"及"双"吡唑啉基化合物的光致发光和电致发光的比较研究 总被引:1,自引:0,他引:1
对7种含"单"或"双"吡唑啉化合物在溶液和在固体器件[ITO/TPD/TPBI-2%EP/TPBI/Mg-Ag]中作为掺杂发光材料的电致发光特性进行了研究.结果表明,由吡唑啉化合物所构成的器件具有优良的电致发光特性.特别是在5-位处联有芳基的双吡唑啉化合物,由于它们具有良好的成膜能力和较高的玻璃化转变温度,因此所制得的器件有很好的稳定性.结果还表明,含双吡唑啉基化合物的荧光量子产率较含单吡唑啉基者为低.由它们所构成器件的电致发光能力也大体反映出相同的趋势. 相似文献
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4-酰基吡唑啉酮是一类含有氮杂环的β-二酮型螯合剂,近几十年来,国内外对该类化合物及其衍生物进行了广泛的研究[1-3].本室验室曾合成了一系列4-苯甲酰基吡唑啉酮缩氨基硫脲及其衍生物,发现这类含硫席夫碱具有光致变色性,并对其变色机理和反应动力学进行了详细研究[4,5].作为工作的继续,我们又合成了1-苯基-3-甲基-4-乙酰基-5-吡唑啉酮缩硫甲基氨基硫脲(PMEP-MTTSC),虽然此化合物不具有光致变色性,但在培养其单晶的过程中,却意外地得到了一种双吡唑啉酮化合物.当用不同的溶剂来培养其单晶时,又得到了这种双吡唑啉酮的一对互变色异构体.反应过程如下: 相似文献
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5-位取代吡唑啉化合物的发光行为及其在电致发光领域中的应用 总被引:7,自引:0,他引:7
合成了一系列5位不同取代的2-吡唑啉化合物,研究了取代基对吡唑啉化合物 物理性质的影响。结果表明,在吡唑啉化合物的5位引入稠环取代基提高了吡唑啉 化合物的熔点;同时,5位取代基的电位性质还影响着化合物的发光行为。DSC差热 分析结果给出1,3-二苯基-5-(9-菲基)-2-吡唑啉(TAP7)的玻璃化温度 (T_g)为96 ℃;并研究了其在电致发光器件上的应用性能。结果表明TAP7是一种具 有高热稳定性的空穴传输及蓝光发光材料。 相似文献
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几种新的4-酰基吡唑啉酮类螯合剂的合成 总被引:41,自引:0,他引:41
4-酰基吡唑啉酮是一类新型的β-双酮型螯合剂.近廿年来,国内外就这类化合物,特别对1-苯基-3-甲基-4-苯甲酰基吡唑啉酮(PMBP)进行了大量的研究工作.PMBP是镧系、锕系和碱土金属元素的优良萃取剂之一,但对一些配位数较高的金属离子,常由于水分子参与配位,萃取效果不佳.例如,PMBP萃取铀酰离子时,由于生成的螯合物中含有两个水分子,具有较大的亲水性,因而分配系数较低.目前对不同取代基的吡唑啉酮的研究还比较少,以1,3-二取代吡唑啉酮为端基的双酰代吡唑啉酮类的合成与 相似文献
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在乙酰乙酸乙酯和氧化亚铜共同催化下, 二-(1,3-二硫环戊烯-2-硫酮-4,5-二硫)合锌酸四乙基铵盐分别与2-碘吡啶(1a)、 3-碘吡啶(1b)和4-碘吡啶(1c)反应, 制得硫酮化合物2,3-二(2-吡啶硫基)-1,3-二硫环戊烯-2-硫酮(2a)、 2,3-二(3-吡啶硫基)-1,3-二硫环戊烯-2-硫酮(2b)和2,3-二(4-吡啶硫基)-1,3-二硫环戊烯-2-硫酮(2c). 在醋酸汞催化下, 硫酮化合物2a, 2b和2c分别被氧化为2,3-二(2-吡啶硫基)-1,3-二硫环戊烯-2-酮(3a)、 2,3-二(3-吡啶硫基)-1,3-二硫环戊烯-2-酮(3b)和2,3-二(4-吡啶硫基)-1,3-二硫环戊烯-2-酮(3c). 以亚磷酸三乙酯为偶联剂, 氧酮化合物3a, 3b和3c分别发生自偶联反应生成2,3,6,7-四(2-吡啶硫基)四硫富瓦烯(4a)、 2,3,6,7-四(3-吡啶硫基)四硫富瓦烯(4b)和2,3,6,7-四(4-吡啶硫基)四硫富瓦烯(4c). 采用核磁共振波谱(NMR)、 傅里叶变换红外光谱(FTIR)和质谱(MS)分析了所合成化合物的结构和组成, 通过X射线衍射分析确认了吡啶基四硫富瓦烯衍生物4b和4c的晶体结构. 循环伏安法研究结果表明, 化合物4a, 4b和4c呈现准可逆的两电子转移过程, 结合量子化学计算, 分析了不同位置取代的吡啶基对四硫富瓦烯电化学电势的影响. 相似文献
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Poumale HM Randrianasolo R Rakotoarimanga JV Raharisololalao A Krebs HC Tchouankeu JC Ngadjui BT 《Chemical & pharmaceutical bulletin》2008,56(10):1428-1430
Two new flavonoid glycosides, namely 3'-(2',4'-dihydroxybenzyloxy)acanthophorin B (1b) and beta,2,3',4,4',6-hexahydroxy-alpha-(alpha-L-rhamnopyranosyl)dihydrochalcone (2) were isolated from the leaves of Psorospermum androsaemifolium together with quercetin (1), acanthophorin B (1a), alpha- (3) and beta-amyrine (3a), vismiaquinone (4), 12-hentriacontanol and hentriacontane. The structures of these secondary metabolites were established using detailed spectroscopic analysis and by comparison with published data. Compounds 1, 1a, 1b, 2, 3, 3a and 4 showed weak antifungal and antibacterial activities. 相似文献
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(tBuC5H4 ) 2 MCl2 (M =Ti(1a) ,Zr(1b) ,Hf(1c) )和 (tBu2 C5H3 ) 2 MCl2 (M =Ti(2a) ,Zr(2b) ,Hf(2c) )可以通过单叔丁基环戊二烯基锂或双叔丁基环戊二烯基锂与MCl4 (M =Ti,Zr,Hf)在四氢呋喃中反应制备得到 ,用IR、1H NMR和EI MS对这些化合物进行了表征 .采用X光单晶结构分析测定了 (tBuC5H4 ) 2 HfCl2 的晶体结构 .六个化合物均具有一定的催化乙烯聚合活性 相似文献
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XU Liang-zhong ZHOU Kai HU Zhi-qiang BI Wen-zhao College of Chemistry Molecular Engineering Qingdao University of Science Technology Qingdao P. R. China 《高等学校化学研究》2006,22(6):765-767
IntroductionAs an important type of fungicide, compoundscontaining 1,2,4-triazole groups have attracted muchattention because they exhibit a certain fungicidal acti-vity againstPuccinia reconditeand also play a role inroot-growth regulation[1—3]. However… 相似文献
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Lobert M Bandmann H Burkert U Büchele UP Podsadlowski V Klärner FG 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(6):1629-1641
The dynamics in the host-guest complexes of the molecular tweezers 1 a,b and clips 2 a,b with 1,2,4,5-tetracyanobenzene (TCNB, 3) and tropylium tetrafluoroborate (4) as guest molecules were analyzed by temperature-dependent 1H NMR spectroscopy. The TCNB complexes of tweezers 1 a,b were found to be particularly stable (dissociation barrier: DeltaG(++)=16.8 and 15.7 kcal mol(-1), respectively), more stable than the TCNB complexes of clips 2 a,b and the tropylium complex of tweezer 1 b (dissociation barrier: DeltaG(++)=12.4, 11.2, and 12.3 kcal mol(-1), respectively). A detailed analysis of the kinetic and thermodynamic data (especially the negative entropies of activation found for complex dissociation) suggests that in the transition state of dissociation the guest molecule is still clipped between the aromatic tips of the host molecule. The 1H NMR analysis of the TCNB complexes 3@1 b and 3@2 a at low temperatures (T<-80 degrees C) showed that 3 undergoes fast rotation inside the cavity of tweezer 1 b or clip 2 a (rotational barrier: DeltaG( not equal)=11.7 and 8.3 kcal mol(-1), respectively). This rotation of a guest molecule inside the host cavity can be considered to be the dynamic equilibration of noncovalent conformers. In the case of clip complex 3@2 a the association and rotational barriers are smaller by DeltaDeltaG(++)=3-4 kcal mol(-1) than those in tweezer complexes 3@1 a,b. This can be explained by the more open topology of the trimethylene-bridged clips compared to the tetramethylene-bridged tweezers. Finally, the bromo substituents in the newly prepared clip 2 b have a substantial effect on the kinetics and thermodynamics of complex formation. Clip 2 b forms weaker complexes with (TCNB, 3) and tetracyanoquinodimethane (TCNQ, 12) and a more stable complex with 2,4,7-trinitrofluoren-9-ylidene (TNF, 13) than the parent clip 2 a. These results can be explained by a less negative electrostatic potential surface (EPS) inside the cavity and a larger van der Waals contact surface of 2 b compared to 2 a. In the case of the highly electron-deficient guest molecules TCNB and TCNQ the attractive electrostatic interaction is predominant and hence responsible for the thermodynamic complex stability, whereas in the case of TNF with its extended pi system, dispersion forces are more important for host-guest binding. 相似文献
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Schiff碱水杨醛缩异烟肼和水杨醛缩4-氨基安替吡啉的合成和晶体结构 总被引:15,自引:0,他引:15
通过水杨醛和异烟肼,4-氨基安替吡啉的缩合反应分别合成了Schiff 碱水杨醛缩异烟肼1,水杨醛缩4-氨基安替吡啉2,并获得其单晶结构。用元素分析,UV-Vis和IR谱进行表征。晶体结构通过X-射线衍射法测定,晶体结构均用直接法解出, 经全矩阵最小二乘法对原子参数进行修正。化合物1:化学计量式为:C13H11N3O2,Mr = 241.25,晶体属于单斜晶系,空间群P21/n, 晶胞参数:a = 8.153(1),b = 15.574(4) , c = 9.554(2) ? b =105.48(1)? V =1169.1(4) ? , Z = 4, Dc =1.371 g/cm3 , m =0.096 mm-1, F(000) = 504,结构偏离因子R = 0.0832, wR = 0.1158,共收集到2384个独立衍射点,其中其I >2(I)的可观测点为2059个。化合物2:化学计量分子式为:C18H17N3O2,Mr = 307.35,晶体属于单斜晶系,空间群P21/n, 晶胞参数: a = 7.597(1),b = 7.500(1) , c = 27.266(5) , b = 95.31(1), V = 1546.7(4) ? , Z = 4, Dc = 1.320 g/cm3 , m = 0.088 mm-1, F(000) = 648,结构偏离因子R = 0.0413, wR = 0.0952,共收集到3282个独立衍射点,其中其I >2(I)的可观测点为2711个。X-射线分析显示化合物1和2的晶体结构均由分子间氢键和-弱相互作用堆积而成的二维层状结构。 相似文献
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三齿单核三(3,5-二甲基-1-吡唑)硼氢钼配合物Tp*Mo(O)Cl2 (1)(Tp*=三(3,5-二甲基-1-吡唑)硼氢HB(C3H(Me2)N2)3)与含硫族元素碳硼烷的锂盐[(THF)2LiE2C2B10H10(THF)]< 相似文献
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间氯苯基锰卟啉-5-氟尿嘧啶配合物的合成及其对癌细胞的抑制活性 总被引:1,自引:1,他引:0
合成了4种新5-氟尿嘧啶-卟啉衍生物:5-[3-(2-(5-氟尿嘧啶-1-基)乙氧基)苯基]-10,15,20-三(3-氯苯基)卟啉(1a)、5-[3-(2-(5-氟尿嘧啶-1-基)乙氧基)苯基]- 10,15,20-三(3-氯苯基)锰卟啉(2a)、5-[3-(3-(5-氟尿嘧啶-1-基)丙氧基)苯基]-10,15,20-三(3-氯苯基)锰卟啉(2b)和5-[3-(4-(5-氟尿嘧啶-1-基)丁氧基)苯基]-10,15,20-三(3-氯苯基)锰卟啉(2c),通过UV-Vis、IR、MS及元素分析表征了它们的结构。 用噻唑蓝法(MTT法)测定了化合物2a、2b和2c对人胃癌细胞株BGC-823的抑制活性。 化合物2b的半数抑制浓度IC50为1.34 μmol/L,表明有一定的细胞毒作用。 相似文献
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Pentacoordinate silicon fluorides L(1)SiF(3) (2a), L(2)SiF(3) (2b), and (L(3)SiF(2))(2) (2c)(2) based on amidinate (L(1) = PhC(N(t)Bu)(2)), guanidinate (L(2) = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinate), and triazapentadienate (L(3) = NC(NMe(2))NC(NMe(2))NAr; Ar = 2,6-(i)Pr(2)C(6)H(3)) ligands were prepared by fluorination of the corresponding chlorosilanes L(1)SiCl(3) (1a), L(2)SiCl(3) (1b), and L(3)SiCl(2) (1c) with Me(3)SnF at ambient temperature. Compounds 1b, 1c, 2a, 2b, and (2c)(2) were characterized by (1)H, (13)C, (19)F, and (29)Si NMR spectroscopic studies. Molecular structures of 1b, 1c, 2a, and (2c)(2) were determined by single crystal X-ray structural analysis. Invariom refinement involving non-spherical scattering factors of the Hansen-Coppens multipole model was performed for 1b. Compound L(3)SiF(2) (2c) is dimeric both in the solid state and in solution, whereas its chloro-analogue 1c is monomeric. The attempted synthesis of diamidinatotetrachlorodisilane by reaction of lithium amidinate with Si(2)Cl(6) led to the formation of the silane (1a) and the silylene L(1)SiCl (3). Reaction of Si(2)Cl(6) with N-heterocyclic carbenes (NHC) afforded NHC adducts of dichlorosilylene and SiCl(4). A one pot method for the preparation of base-stabilized silylenes from Si(2)Cl(6) is discussed. 相似文献