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861.
Synthesis of novel allyl palladium complexes bearing purine based NHC and a water soluble phosphine and their catalytic activity in the Suzuki‐Miyaura coupling in water
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Thomas Scattolin Luciano Canovese Fabiano Visentin Stefano Paganelli Patrizia Canton Nicola Demitri 《应用有机金属化学》2018,32(2)
We have synthesized and fully characterized some novel allyl palladium complexes stabilized by mixed spectator ligands, namely the water soluble sodium 3,3′,3″‐phosphinetriyltribenzenesulfonate, (TPPTS) and three carbenes derived from differently alkylated natural xanthines. In order to explore their potential applications we have tested their catalytic activity in the Suzuki‐Miyaura coupling of para‐bromoacetophenone with phenyl boronic acid, chosen as standard reaction. Only one of the complexes under study displays a remarkable stability in water and catalytic activity. We have therefore undertaken a catalytic investigation. These results are reported in the present paper together with the solid state structural characterization of a silver precursor of the palladium allyl complexes. 相似文献
862.
Susana Ibez Eduardo Peris 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6765-6769
A trigonal‐prismatic hexagold cage was obtained by combining a triphenylene‐tris(N‐heterocyclic carbene) ligand and a carbazolyl‐bis(alkynyl) linker. The metallocage has a slot‐like cavity with a volume of about 300 Å3. The cage was used for the recognition of several polycyclic aromatic hydrocarbons. Due to the perfect dimensional match, the supramolecular complex shows a very high affinity for trapping coronene. 相似文献
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Fabiano Barbieri Gonzaga Júlio Cesar Dias Diana Jehnert Barbara Werner Karin Schräpler Leoš Vyskočil 《Electroanalysis》2013,25(8):1955-1959
This work presents a new differential potentiometric cell for the standardization of pH buffer solutions and its evaluation, by means of a bilateral interlaboratory comparison, in relation to a traditional Baucke cell. The results obtained with the two cells were exactly the same for three of the pH buffer solutions analyzed (1.68, 4.01, and 6.86) and similar to each other for the remaining buffer solution (9.18). The new cell showed an average measurement time of only 21 minutes, in comparison with one to three hours for other cells described in the literature (including the Baucke cell). 相似文献
866.
Synthesis,characterization and assessment of the cytotoxic activity of Cu(II), Fe(III) and Mn(III) complexes of camphoric acid‐derived salen ligands
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Dina Murtinho Zênis N. da Rocha Ana Salomé Pires Roberto P. Jiménez Ana Margarida Abrantes Mafalda Laranjo Ana Catarina Mamede João Eduardo Casalta‐Lopes Maria Filomena Botelho Alberto A. C. C. Pais Sandra C. C. Nunes Hugh D. Burrows Telma Costa M. Elisa Silva Serra 《应用有机金属化学》2015,29(7):425-432
Novel Cu(II), Fe(III) and Mn(III) salen‐type metal complexes from (1R,3S)‐N,N′‐bis[salicylidene]‐1,3‐diamino‐1,2,2‐trimethylcyclopentane were synthesized and screened for their in vitro cytotoxic activity against three human cancer cell lines: melanoma, colorectal and breast. In vitro experiments carried out with the three metal complexes show that the copper complex exhibits the highest cytotoxic activity towards all cell lines studied, presenting IC50 values of 3.32–6.71 μM. A significant improvement in the anti‐proliferative effect, by 20‐fold, is observed with this complex when compared with conventional chemotherapy. The relationship between structure, redox characteristics and biological activity in human cancer cell lines was evaluated for the most efficient Cu(II) complex and associated with theoretical calculations. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
867.
Beatriz M. de Campos Paulo S. Calefi Katia J. Ciuffi Emerson H. de Faria Lucas A. Rocha Eduardo J. Nassar Jorge V. L. Silva Marcelo F. Oliveira Izaque A. Maia 《Journal of Thermal Analysis and Calorimetry》2014,115(2):1029-1035
The combination of sol–gel methodology with rapid prototyping (RP) produces functionalized 3D structures with potential applications in various fields. However, this combination has been little explored. In this paper, we used the sol–gel method to deposit vanadium isopropoxide onto polyamide (PA12) constructed by RP and pretreated with acetic acid, to obtain a functionalized substrate with new thermal, physical, and chemical properties. Vanadium isopropoxide (one, five, or ten layers) was deposited onto the PA12 piece by dip-coating. We characterized the coated PA12 by thermal analyses, X-ray diffraction, and infrared spectroscopy, which revealed that V=O and Si–O–Si groups exist on the PA12 surface. PA12 coating with vanadium isopropoxide enhanced the decomposition temperature. Differential scanning calorimetry revealed increased fusion and decomposition enthalpy as a function of the PA12 coating. Therefore, deposition of vanadium isopropoxide onto PA12 pretreated with acetic acid improves the thermal stability of PA12 prepared by RP. 相似文献
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Heriberto Espinoza-Gomez Raudel Ramos-Olmos Cesar Garcia-Rios Shui Wai Lin Eduardo Rogel-Hernandez Ana Ames-Lopez 《Heat and Mass Transfer》2007,43(10):1003-1008
The conduction properties of HMC polymer gel prepared by the phase inversion method were investigated through the diffusion
coefficient in order to confirm the conduction mechanism. The solution introduced in the polymer is stored in the pores and
then penetrates into the polymer chains. For swelling the polymer network. A model describing the swelling hidroxy-methyl
cellulose is presented. The model is used to predict the type liquid–liquid phase separation (instantaneous or delayed) that
occurs when HMC-PVPD-Solvent-Water casting solutions are immersed in a gelation bath. The model includes the thermodynamic
interactions parameters and the transport parameters. The predictions of the model agree with the experimental observations. 相似文献