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101.
Ion L Morales D Nieto S Pérez J Riera L Riera V Miguel D Kowenicki RA McPartlin M 《Inorganic chemistry》2007,46(7):2846-2853
Compounds [Mo(CO)4(N-N)] (N-N = 4,4'-bis((4-methylphenyl)carbamoyl)-2,2'-bipyridine, bipy', 1; or 2,2'-biimidazole, H2biim, 2), [MoCl(eta3-methallyl)(CO)2(N-N)] (N-N = bipy', 3; H2biim, 4), and [Mo(eta3-methallyl)(CNtBu)(CO2)(N-N)]BAr'4 (Ar' = 3,5-bis(trifluoromethyl)phenyl; N-N= bipy', 5; H2biim, 6) were synthesized and characterized, and their behavior toward anions was investigated in solution (IR and 1H NMR) and in solid state (X-ray diffraction). 相似文献
102.
Rusu Mihai Lucian Marutoiu Constantin Sandu Ion Tita Dumitru Gogoasa Ioan Barbu Constantin-Horia Popescu Andreea 《平面色谱法杂志一现代薄层色谱法》2007,20(2):139-140
JPC – Journal of Planar Chromatography – Modern TLC - Samples of clove, nutmeg, and cinnamon have been extracted by maceration with ethanol for 24 h and with aqueous ethanol 48 h.... 相似文献
103.
104.
Peyman Sakhaii Ion Neda Matthias Freytag Holger Thnnessen Peter G. Jones Reinhard Schmutzler 《无机化学与普通化学杂志》2000,626(5):1246-1254
The acid‐catalyzed (with HCl) condensation reactions of resorcinol ( 1 ) with 1‐naphthaldehyde ( 2 ) and isobutyraldehyde ( 3 ) furnished the tetrameric macrocyclic compounds 4 and 6 . Detailed NMR‐investigations of the acetylated tetrameric species 5 surprisingly support a structure not in agreement with the expected all‐cis conformation. The chair conformation (C2h symmetry) of the acetylated derivative 5 was established through a crystal X‐ray diffraction study. The naphthyl substituents are arranged in trans position above and below the plane made up by the resorcinol units. The reaction of resorcinol 1 with isobutyraldehyde, in accord with expectation, led to the calix[4]resorcinaren ( 6 ). The 1H NMR spectra of compound 6 and 7 appeared at room temperature as broad signals, indicating a conformation of C2v symmetry. The reaction of the C‐methyl‐tetrakis‐P‐(chlorodioxaphosphocin)‐calix[4]resorcinarenes ( 8 ) and ( 10 ) with suitable N‐trimethylsilyl organic amines were conducted in tetrahydrofuran suspension, furnishing the P–N‐substituted calix[4]resorcinarenes ( 9 ) and ( 11 ). While in the complexation of C‐methyl‐tetrabromotetrakis‐P‐(dimethylaminodioxaphosphocin)‐calix[4]resorcinarene ( 13 ) with (tht)AuCl (tht = tetrahydrothiophene) the expected, neutral tetra‐substituted complex 15 was formed, the reaction of 13 with moist acetonitrile led to the anionic atomic framework 14 . X‐ray structure determinations of the complexes 14 and 15 show that both possess the cone conformation. In the gold complex 15 , the Au–Cl groups form a loose aggregate, with three Au…Cl contacts of 316–340 pm; one of the groups points towards the centre of the cone. The copper(I) complex 14 displays crystallographic mirror symmetry, with a central Cu4Cl5 unit involving tetrahedrally coordinated copper. 相似文献
105.
Roiban GD Serrano E Soler T Aullón G Grosu I Cativiela C Martínez M Urriolabeitia EP 《Inorganic chemistry》2011,50(17):8132-8143
Orthopalladated complexes derived from (Z)-2-aryl-4-arylidene-5(4H)-oxazolones have been prepared by reaction of the oxazolone with palladium acetate in acidic medium. The reaction is regioselective, only the ortho C-H bond of the arylidene ring being activated, producing a six-membered ring. The scope and reaction conditions of the orthopalladation are dependent on the acidity of the solvent. In CF(3)CO(2)H a large number of oxazolones can be metalated under mild conditions. As acidity decreases a lesser number of oxazolones can be efficiently palladated and harsher conditions must be used to achieve similar yields. The C-H bond activation in acidic medium agrees with an ambiphilic mechanism, as determined from kinetic measurements at variable temperature and pressure for different oxazolones substituted at the arylidene ring. The mechanism has been confirmed by density functional theory (DFT) calculations, where the formation of the six-membered ring is shown to be favored from both a kinetic and a thermodynamic perspective. In addition, the dependence of the reaction rate on the acidity of the medium has also been accounted for via a fine-tuning between the C-H agostic precoordination and the proton abstraction reaction in the overall process occurring on coordinatively saturated [Pd(κ(N)-oxazolone)(RCO(2)H)(3)](2+). 相似文献
106.
Monica Mihorianu M Heiko Franz Peter G Jones Matthias Freytag Gerhard Kelter Heinz‐Herbert Fiebig Matthias Tamm Ion Neda 《应用有机金属化学》2016,30(7):581-589
A series of Au(I) complexes ( 12 , 13 , 14 , 15 , 16 ) and Ag(I) complexes ( 17 , 18 , 19 , 20 ) derived from imidazo[1,5‐a]pyridin‐3‐ylidenes were synthesized from AuCl(SMe2) or by reacting silver(I) acetate with 2,5‐dimethylimidazo[1,5‐a]pyridin‐2‐ium iodide or imidazo[1,5‐a]pyridin‐2‐ium salts, and were characterized using NMR spectroscopy, mass spectrometry and elemental analyses. In addition, the Au(I) complex 13 and the Ag(I) complex 19 were characterized using single‐crystal X‐ray diffraction. Using paclitaxel as a standard, all Au(I) and Ag(I) N‐heterocyclic carbene complexes were evaluated for their in vitro anti‐tumour activity against 12 cell lines using a monolayer cell survival and proliferation assay. The highest anticancer activity was found for complexes 15 , 13 and 14 with mean IC50 values of 10.09, 10.42 and 12.28 μM, respectively. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
107.
108.
Molecular rotors: design, synthesis, structural analysis, and silver complex of new [7.7]cyclophanes
Bogdan N Grosu I Benoît G Toupet L Ramondenc Y Condamine E Silaghi-Dumitrescu I Plé G 《Organic letters》2006,8(12):2619-2622
New molecular rotors, [7.7](2,6)pyridinocyclophanes (monomers and dimers) embedding 1,3-dioxanes in the bridges, were investigated by variable-temperature NMR, molecular modeling, and single-crystal X-ray diffractometry. The nitrogen-inside rotation of the pyridine ring is more hindered in the derivatives with longer distance between the bridges (i.e., para > meta and 2,6-pyridylene > ortho) and can be chemically stopped by complexation with CF(3)SO(3)Ag. [structure: see text] 相似文献
109.
Ion Marian Olaru Adrian Nicolae Branga 《Journal of Fixed Point Theory and Applications》2018,20(2):78
In this paper, we prove some coincidence and common fixed point theorems for self-maps satisfying contractive conditions in a \(D^*\)-quasimetric space. 相似文献
110.
Ion Grama Jean-Marie Tricot Jean-François Petiot 《Comptes Rendus Mathematique》2011,349(13-14):807-811
Within the framework of a survival analysis model with censored life time data and an explanatory covariate, our goal is to predict the survival probability beyond the largest observed time. A Cox model with a constant underlying hazard function is proposed to adjust the tail of the life time distribution. Under some regularity conditions, we prove that the parameter estimators are convergent. 相似文献