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1.
IntroductionTheabilityofdithiocarbamate(dtc)bindingtometalshasbeenknownformanyyears .Itformschelateswithvirtu allyalltransitionmetals.1Thebidentateanionisalsowellknownasabridgebetweentwotransitionmetalcenters.2 Wa ter solubledialkyldithiocarbamatecomplexes… 相似文献
2.
N. V. Chizhova O. M. Kulikova N. Zh. Mamardashvili 《Russian Journal of General Chemistry》2013,83(11):2108-2111
The interaction of 5,10,15,20-tetraphenylporphyrin, 5,10,15,20-tetra-(4-chlorophenyl)porphyrin, 2-bromo-5,10,15,20-tetraphenylporphyrin, and 2,3,12,13-tetrabromo-5,10,15,20-tetraphenylporphyrin with platinum(II) chloride in boiling phenol has been studied. The corresponding platinum(II) porphyrinates have been synthesized; their subsequent treatment with bromine in chloroform resulted in platinum(IV) porphyrinates. The Pt(II) and Pt(IV)(Br)2 porphyrinates have been identified by elemental analysis, electron absorption, IR, and 1H NMR spectroscopy. 相似文献
3.
《Tetrahedron: Asymmetry》1999,10(10):1969-1977
Pseudomonas cepacia lipase (PSL) efficiently catalyses the kinetic resolution of (±)-cis- and (±)-trans-1-aminoindan-2-ol through the O-acylation reaction of the corresponding N-benzyloxycarbonyl derivative using vinyl acetate as the acyl donor. In a similar way, cis-N-Cbz-2-aminoindan-1-ol is resolved when isopropenyl acetate is used as the acylating agent. The enantioselectivity of the reaction was lower for (±)-trans-N-Cbz-2-aminoindan-1-ol due to the different steric requirements for the two conformers of this substrate. 相似文献
4.
《Journal of Coordination Chemistry》2012,65(11):1811-1819
Trichloro- and triisopropoxy-niobium(V) and tantalum(V) alkylene dithiophosphates, (M = Nb(V) or Ta(V); G =–CHMeCHMe–,–CMe2CMe2–,–CH2CMe2CH2–,–CH2CEt2CH2–or–CMe2CH2CHMe–and X = Cl or OPri) have been synthesized by reaction of metal(V) chloride, MCl5, or triisopropoxymetal(V) dichloride, (PriO)3MCl2, with the sodium salts of O,O′-alkylene dithiophosphoric acids, in 1 : 2 molar ratio in THF under anhydrous conditions. These pink-purple or light-yellow compounds are viscous, semi-solid or solid, hydrolyzable and soluble in common organic solvents. These compounds have been characterized by elemental analyses, molecular weight determinations and spectral studies like IR and heteronuclear NMR (1H, 13C and 31P), which indicated a bidentate mode of chelation of dithio ligands, leading to a pentagonal bipyramidal geometry around the niobium(V) or tantalum(V) centers. 相似文献
5.
A. A. S. Elkhaldy A. R. Hussien A. M. Abu Shanab M. A. Wassef 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):589-597
Abstract Reactions of O,O′-dialkyl and alkylene dithiophosphoric acids with bis (cyclopentadienyl) titanium(IV) and zirconium (IV) dichloride in a 1:1 molar ratio in refluxing benzene proceeds with elimination of HCl and formation of the substituted derivatives, Cp2MCl[S2P(OR)2] (where R = Et, Pr-n, Pr-i, Bu-i and Ph), Cp2MCl[S2POGO] (where G = ?CH2CMe2CH2?, ?CH2CEt2CH2? and ?CMe2CMe2?), (M = Ti and Zr). The complexes are dark red and yellow solids, soluble in common organic solvents and monomeric in nature. These have been characterized on the basis of elemental analyses, molecular weight determinations, IR, and NMR (1H, 13C, and 31P). GRAPHICAL ABSTRACT 相似文献
6.
A. N. Blinnikov S. Kulikov N. N. Makhova L. I. Khmel'nitskii 《Russian Chemical Bulletin》1996,45(7):1692-1698
A general and simple preparative method for the synthesis of -hydroxyalky(benzyl)furazan and -furoxan derivatives is proposed, The method involves reduction of acyl or ethoxycarbonyl substituents in these heterocyclic compounds with NaBH4 in ethanol. Based on the alcohols thus prepared, a number of previously unknown functional derivatives (-nitroxyalkyl--haloalkyl-, and -azidoalkylfurazans and -furoxans) have been synthesized.Translated fromInvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7. pp, 1782–1788, July, 1996. 相似文献
7.
Fullerenesareakindofcarbonallotropesfoundrecently,andhavedistinctivestructuresandproperties.Forexample,C60hasafootballlikecarbonskeletonwith20sixmemberedrings,12fivememberedringsandalargeballshelllikeπbondsystem.Alternatively,C70hasanellipsoidlikecarbonskel… 相似文献
8.
Atomization energies at 0 K and heats of formation at 0 and 298 K are predicted for the neutral and ionic N(x)F(y) and O(x)F(y) systems using coupled cluster theory with single and double excitations and including a perturbative triples correction (CCSD(T)) method with correlation consistent basis sets extrapolated to the complete basis set (CBS) limit. To achieve near chemical accuracy (±1 kcal/mol), three corrections to the electronic energy were added to the frozen core CCSD(T)/CBS binding energies: corrections for core-valence, scalar relativistic, and first order atomic spin-orbit effects. Vibrational zero point energies were computed at the CCSD(T) level of theory where possible. The calculated heats of formation are in good agreement with the available experimental values, except for FOOF because of the neglect of higher order correlation corrections. The F(+) affinity in the N(x)F(y) series increases from N(2) to N(2)F(4) by 63 kcal/mol, while that in the O(2)F(y) series decreases by 18 kcal/mol from O(2) to O(2)F(2). Neither N(2) nor N(2)F(4) is predicted to bind F(-), and N(2)F(2) is a very weak Lewis acid with an F(-) affinity of about 10 kcal/mol for either the cis or trans isomer. The low F(-) affinities of the nitrogen fluorides explain why, in spite of the fact that many stable nitrogen fluoride cations are known, no nitrogen fluoride anions have been isolated so far. For example, the F(-) affinity of NF is predicted to be only 12.5 kcal/mol which explains the numerous experimental failures to prepare NF(2)(-) salts from the well-known strong acid HNF(2). The F(-) affinity of O(2) is predicted to have a small positive value and increases for O(2)F(2) by 23 kcal/mol, indicating that the O(2)F(3)(-) anion might be marginally stable at subambient temperatures. The calculated adiabatic ionization potentials and electron affinities are in good agreement with experiment considering that many of the experimental values are for vertical processes. 相似文献
9.
《结构化学》2016,(9)
The interaction of Hg(Ⅱ), Cu(Ⅰ) and Ag(Ⅰ) with dipyridine quinoxaline ligand 2,3-bis(2-pyridyl)quinoxaline(DPQ) were investigated, and three new complexes have been synthesized and characterized. Complex 1 exhibits a 0D dual-core structure, complex 2 is a 0D tetra nuclear case based on a dual-core Cu unit, and complex 3 shows a one-dimensional pipeline structure. Furthermore, the optical properties of complex and DPQ were also investigated, and the results showed that the fluorescence intensity of complexes was weaker than that of ligand DPQ. 相似文献
10.
Ping ZHENG Wei Lin SUN* Zhi Quan SHEN Department of Polymer Science Engineering Zhejiang University Hangzhou 《中国化学快报》2005,(10)
In recent years,the organic ferromagnets have drawn growing attention due to their characteristics of structural diversities,low density,and readily processing1-3.Design and synthesis of magnetic polymers are one of great challenges in today′s magnetic material research,and some significant achievements have been made in this field4,5.In this article,we describe the synthesis of acrylamide-type polymer with pendent thiazolyl groups(Scheme1).The as-prepared polymer exhibited better solubility … 相似文献
11.
Vera R. L. Constantino Luiz F. C. de Oliveira Paulo S. Santos Henrique E. Toma 《Transition Metal Chemistry》1994,19(1):103-107
Summary The synthesis, spectra and electrochemistry of [Ru(bipy)2-(picOH)]+ and -picO-[Ru(bipy)2]2
2+ (bipy = 2,2-bipyridine and picOH = 3-hydroxypicolinate ion) are described. The spectroscopic properties in the visible region are dominated by the intense Ru bipy chargetransfer transitions. In the binuclear complex, the two [Ru(bipy)2L]2+ moieties are nonequivalent, exhibiting E
1/2 = 0.69 and 1.20 V versus s.h.e. The partially oxidized species exhibits a weak intervalence transfer band at 1085 nm, and is consistent with a Robin-Day class II mixed valence complex. 相似文献
12.
A total synthesis of (±)-boschnialactone ( 1 ) and (±)-tertahydroanhydrodesoxyaucubigenin ( 2 ) is described and trisubstitued cyclopentenoid 3 is a key intermediate. 相似文献
13.
Chen ZH Zhang YQ Chen ZM Tu YQ Zhang FM 《Chemical communications (Cambridge, England)》2011,47(6):1836-1838
The first total synthesis of polycyclic Stemona alkaloid maistemonine has been achieved. The efficient approach features a stereoselective intramolecular Schmidt reaction, a ketone-ester condensation, and a Reformatsky reaction. Additionally, another Stemona alkaloid stemonamide was divergently synthesized from a common intermediate. 相似文献
14.
Xiao Yan ZHANG Xin GAO Yan LI Xiao Dong FAN Northwestern Polytechnical University Xi’an School of Chemical Engineering Northwest University Xi’an The Hospital Lab New York University 《中国化学快报》2006,(2)
Blood may contain high proportion of the toxic and essential metals.Blood is responsiblefor the transport of ion of such metals.The organs such as the kidney,liver and placentaare exposed to a large proportion of the metals which enter the blood and may b… 相似文献
15.
E. Havránek A. Bumbálová P. Křenek M. Strašák M. Beláková M. Komová 《Journal of Radioanalytical and Nuclear Chemistry》1991,155(4):253-261
The preparation of99mTc-Sn-EBV and99mTC-Sn-EBA is described. Different parameters affecting the labeling efficiency (ligand concentration, pH, molar ligand: reducing agent ratio) as well as the time-dependent stability of labeled compounds were investigated. Preliminary biodistribution studies in Wistar rats showed accumulation of the above mentioned compounds in kidneys. 相似文献
16.
Nigamananda Das 《Transition Metal Chemistry》1993,18(4):372-376
Summary The kinetics of reversible complexation of Ni(OH2)
inf6
sup2+
with oxygen-bonded glycinatocobalt(III) substrates N4-Co(glyH)gly2+ [N4 = (en)2 or trien; glyH = H3N+CH2-COO–] have been investigated by the stopped-flow technique in the 20–35° C range, at pH = 6.08–6.82 and I = 0.3 mol dm–3. The formation of N4Co(glyH)glyNi4+ occurred via the reaction of Ni(OH2)
inf6
sup2+
with the deprotonated form of the cobalt(III) substrates, N4Co-(glyH)gly2+. The rate and activation parameters for the formation and dissociation of the binuclear species are reported. The formation rate constants k
f (at 25° C), activation enthalpy and entropy H
, S
for N4Co-(glyH)glyNi4+ are 320±49, 341 ± 52dm3mol–1 s–1, 78 ± 7, 79 ± 5 kJmol–1 and 64 ± 24, 69 ± 18 JK–1 mol–1 for the ethylenediamine and triethylenetetraminecobalt(III) substrates, respectively. This result indicates that the rate and activation parameters are virtually independent of the nature of N4 moities, which strongly suggests that the formation of mono-bonded species occurs via entry of one of the pendant NH2 groups into the coordination sphere of nickel(II) via a rate-limiting Ni-OH2 bond dissociation mechanism (Id). The binuclear species exist in dynamic equilibrium between the monodentate and chelated forms, with the chelate form predominating. The low values of spontaneous dissociation rate constant for the binuclear species (k
r- 0.095–1 at 25° C) in comparison with the high values of dissociation rate constants of monodentate nickel(II) complexes reported in the literature also support the chelate nature of the binuclear species. 相似文献
17.
Using density functional theory (DFT) method with 6-31G* basis set, we have carried out the optimizing calculation of geometry, vibrational frequency and thermodynamical stability for(AIN)n+ and (AIN)n- (n =1-15) clusters. Moreover, their ionic potential (IP) and electron affinity(EA) were discussed. The results show that the electrical charge condition of the cluster has a relatively great impact on the structure of the cluster and with the increase of n, this kind of impactis reduced gradually. There are no AI-AI and N-N bonds in the stable structure of (AIN)n+ or (AIN)n-, and the AI-N bond is the sole bond type. The magic number regularity of (AIN)n+, and (AIN)n- is consistent with that for (AIN)n, indicating that the structure with even n such as 2, 4,6, … is more stable. In addition, (AIN)10 has the maximal ionization power (9.14 eV) and the minimal electron affinity energy (0.19 eV), which manifests that (AIN)10 is more stable than other clusters. 相似文献
18.
A. N. Azizova D. B. Tagiev Sh. G. Kasumov Kh. I. Gasanov 《Russian Journal of General Chemistry》2018,88(3):505-508
The platinum(II) and palladium(II) complexes [Pt6(SCH2CH2NH2)8]Cl4 and [Pd6(SCH2CH2OH)8 Cl4· 5H2O with mercamine and β-mercaptoethanol, respectively, were synthesized. It was found on the basis of the comparison of IR and X-ray electron spectra of the ligands and complexes, and also of the data of X-ray diffraction analysis that the bidentate coordination of ligands through sulfur and nitrogen atoms is realized in the platinum(II) complex. In the palladium(II) complex β-mercaptoethanol is coordinated in a mixed-mode type. In both complexes sulfur atoms of the ligands occupy a bridging position. 相似文献
19.
Zhaoye Li Rujiang Ma Ang Li Huan He Yingli An Linqi Shi 《Colloid and polymer science》2011,289(13):1429-1435
In this paper, multicolored micelles were prepared by coordination of lanthanide(III) (europium(III) (Eu(III)) and terbium(III)
(Tb(III))) ions with block copolymer in different molar ratios of n
Eu(III)/n
Tb(III). The micelles formed by polymer–Eu(III)/Tb(III) could emit higher quantum yield luminescence than the mixture of polymer–Eu(III)
micelles and polymer–Tb(III) micelles. The micelles containing Eu(III) and Tb(III) could emit a yellow-green color, and the
intensity varied with the molar ratios of n
Eu(III)/n
Tb(III). In the constant concentrations of Eu(III) and 1,10-phenanthroline (Phen), the intensity of 5D0→7F2 increased with the addition of Tb(III), and the intensity of 5D4→7F5 decreased with the increasing of Eu(III) in the constant concentrations of Tb(III) and Phen. All the multicolored micelles
could be spin-coated as intensity-tunable films. 相似文献
20.
Raj Kumar Dubey 《Transition Metal Chemistry》1993,18(2):243-247
Summary
-Diketonato- and phenoxo-derivatives of mono(dizirconium-ennea-isopropoxy) copper(II), [Cu{Zr2(OPr-i)9}-(RCOCHCOR)] and [Cu{Zr2(OPr-i)9}(-OAr)], have been prepared by the interaction of K(RCOCHCOR) or KOAr (1 mol) [R = R = Me (1a); R = R = CF3 (1b); R = Me, R = CF3 (1c); OAr = 2,6-Me2C6H3O (2a), 3,5-Me2C6H3O (2b), p-ClC6H4O (2c)] with [Cu{Zr2-(OPr-i) 9}(-Cl)] (1 mol) in PhH. Alcohol interchanges of the derivative [Cu{Zr2(OPr-i)9}(-Cl)] have also been studied. These new compounds have been characterized by elemental analyses, i.r., electronic and e.s.r. spectra, and magnetic susceptibility measurements. The studies indicate a distorted octahedral geometry around CuII. 相似文献