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报道了2个取代三联吡啶配体(4′-苯基-2,2′:6′,2″-三联吡啶(L1)和4′-二茂铁基-2,2′:6′,2″-三联吡啶(L2)的Co(Ⅱ)配合物(Co(Ⅱ)(L1)2)(ClO4)2.4CH3CN(1)和(Co(Ⅱ)(L2)2)(ClO4)2H2O(2)的合成及配体L2的配合物1和配合物2的晶体结构,电化学研究表明:在配合物2中,由于Co^2+的作用,二茂铁基的氧化电位较配体L2中的二茂铁 相似文献
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三(2—吡啶甲基)甲烷为配体的双金属配合物的制备及其催化性能研究 总被引:1,自引:0,他引:1
报道了一种新的以三(2-吡啶甲基)甲烷为配体,以铑为主催化活性中心,并辅以其它金属为辅助催化的双金属配合物该配合物在相对温和的条件下,可迅速催化甲醇羰基化为醋酸,及醋酸甲酯羰基化为醋酐。实验结果证明,第二种金属的引入提高了配合物的催化活性,这种催化活性的提高因第二种金属的不同而有所差异。另外,根据配体的结构阐述了其对羰基化反应的作用机理。 相似文献
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利用双齿膦配体1,1-双(二苯基膦)甲烷和1,2-双(二苯基膦)乙烷的还原性以及硝酸配体的易变特性,通过配体还原反应和配体取代反应,于甲醇溶剂中,在dppm和dbbe的存在下,合成了两个双核铜(I)配合物[Cu(dppm)(L)]]2(L分别为BH4和CIO4)和两个单核铜(I)配合物[Cu(dppe)(L)](L分别为BH4和CIO4)。本文又采用两种不同方法合成了两个合成了两个混配铜Ⅱ)配合物 相似文献
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尾式金属卟啉配合物的研究(Ⅲ)—咪唑基尾式卟啉及其铁(Ⅲ… 总被引:9,自引:0,他引:9
合成了咪唑基尾式卟啉-5-邻[4-(1-咪唑基)丁氧基]苯基-10,15,20-三苯基卟啉及其铁(Ⅲ)配合物。以元素分析,质谱,^1 H NMR,IR和紫外可见吸收光谱等进行了表征,初步研究了在氯仿和苯中某些含氮配体与铁(Ⅲ)配合物的轴向配位性质,表明,Fe(Ⅲ)Cl通常与含氮配体生成低自旋的六配位加合物,但在苯溶液中与咪唑作用时,一定条件下还能生成稳定的高自旋五配位加合物。 相似文献
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金属有机配合物的非线性光学特性 总被引:4,自引:1,他引:4
从过渡金属有机配合物的中心金属、配体和几何结构的多样性、多变的金属氧化态和金属与配体的电子供-受作用评述了金属有机配合物的二阶、三阶非线性光学效应的分子结构特征和最新进展。参考文献26篇。 相似文献
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TTF·M(dmit)2型电荷转移配合物的合成及其拉曼光谱 总被引:2,自引:0,他引:2
合成了8种四硫富瓦烯·二-(1,3-二硫杂环戊-4-烯-2-硫酮-4,5-二巯基)金属(缩写为TTF·M(dmit)-2)电荷转移配合物,其中7种配合物为首次合成,拉曼光谱的研究结果表明,对同一种电子受体,电子给体的还原电势Ep越小,配合物的电荷转移度ρ值越大。 相似文献
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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%. 相似文献
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Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments. 相似文献
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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. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 相似文献
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KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. 相似文献
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N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
The review contains a concise historical account and information on the most significant researches undertaken by the staff
at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry
of Heterocyclic Compounds.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008. 相似文献
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Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products. 相似文献
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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. 相似文献
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《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative. 相似文献