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本文合成了11种稀土与α-萘乙酸的配合物。元素分析结果表明配合物的组成为RE(C12H9O2)3.2H2O(RE=La,Ce,Pr,Nd,Sm,Eu,Gd,Dy,Er,Yb,Y),并通过配合物的IR,UV,H-NMR,TG-DTA,XPS,磁化率,摩尔电导及溶解性的研究。 相似文献
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RECl3与丝氨酸配合行为的研究 总被引:1,自引:0,他引:1
李仲谨 《高等学校化学学报》1998,19(6):942-945
依据相平衡结果,于水中合成了RE(Ser)Cl3.3H2O和RE(Ser)2Cl3.5H2O(RE=La-Nd,Sm-Gd,Dy,yb,Y)等20种固态配合笺,利用化学分析,摩尔电导,IR、UV、FS、X射线衍射分析及TG-DTG等手段对配合物进行了表征。 相似文献
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制备了RECl3·3H2O(RE=Pr、Gd)与18C6的固态配合物,其化学组成为:RECl3·18C6·3H2O.对其进行了IR、溶解度、DTG和TG分析.推测了热分解机理.测量了298.15K时18C6及两种配合物在无水乙醇中的积分溶解热,以及RECl3·3H2O在18C6-C2H5OH溶液中的溶解配位热效应.依据本文所设计的热化学循环,求得了RECl3·3H2O(s)与18C6(S)生成RECl3·18C6·3H2O(S)的反应热及两种配合物的标准生成焓. 相似文献
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合成了通式为K15H3〔Ce(P2W16VO61)2〕.61H2O、K15H4〔Ln(P2W16VO61)2〕.xH2O(Ln=La^3+,Pr^3+,Nd^3+,Sm^3+,Eu^3+,Gd^3+,Dy^3+,Yb^3+)的9种镧系元素Dawson结构的钨钒磷四元杂多配合物,并用IR、UV、NMR、ESR、XRD、TG-DTA等对其结构和性质进行子研究。该类配合物具有与K16〔Ce(P2W17O 相似文献
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稀土组氨酸配合物的合成和性质研究 总被引:1,自引:0,他引:1
本文合成了十二个稀土与L-组氨酸(L-His)的固体配合物,元素分析结果表明配合物的组成为Ln(His)3(NO3)32H2O(Ln=Y,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Er,Tm)。并通过配合物的IR、UV、H-NMR、TG-DTA、磁化率及在水中的摩尔电导等的研究,表征了这些配合物的物理化学性质,结果表明稀土组氨配合物中配体通过羟基氧原子与镧系离子配位。 相似文献
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以邻苯二酚、2-氯乙醇、二乙醇胺和溴乙酸为原料,合成了一个新的配体——N-乙酸取代苯并氮杂冠醚。在无水乙醇中经置换反应,制得了九种稀土硫氰酸盐冠醚固体配合物,经元素分析确定其组成为RE(SCN)2·L·2H2O(RE=La,Pr,Nd,Sm,Eu,Gd,Er,Y;L=N-乙酸取代苯并氮杂冠醚)。用IR、UV-Vis和电导测定等方法,研究了配合物的配位结构和性质。 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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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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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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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