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Constantin Mateescu Ecaterina Princz Gilles Bouet Mustayeen A. Khan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):947-958
The complex formation equilibrium of ethylenediaminetetramethylenephosphonic acid (EDTMP, H8L) with iron (III) has been studied potentiometrically at 25°C and an ionic strength of 0.2 M (NaCl). The successive protonation constants of ligand EDTMP and the complex formation constants were determined with the PSEQUAD program. Keeping in view the biological studies, the speciation in the system Fe (III)—EDTMP was calculated and drawn with the HySS computer program, and pFe values are compared. 相似文献
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The addition reaction of ethylmagnesium bromide to the triple bond of the compounds of general formula EtSCH2CCCH2Y (where Y is the basic group OH, OR, NR2, or SEt) is very weakly activated by the thioether group. Catalysis by magnesium impurities may be involved.With 1-ethylthio-4-dialkylamino-2-butynes (Y NR2), (E) trisubstituted ethylenic compounds are selectively obtained. The reaction more readily occurs after the addition of cuprous chloride to the Grignard solution, and then its stereoselecitvity may be reversed. 相似文献
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Leleu S Penhoat M Bouet A Dupas G Papamicaël C Marsais F Levacher V 《Journal of the American Chemical Society》2005,127(45):15668-15669
A new and unprecedented exploitation of quinolinium thioester salts 2 in peptide bond formation is reported. These synthetic tools were assessed during the preparation of a number of dipeptides 3a-f obtained in good yields with complete stereochemical integrity. A sequential mechanism related to a prior amine capture strategy is well-established. Additionally, a tripeptide 3g was prepared according to a "safety-catch" approach, thus demonstrating the important potential of these new synthetic tools in the design of new safety-catch linkers exploitable in Solid-Phase Peptide Synthesis (SPPS). 相似文献
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Lin Zhou Lei Huang Nathalie Bouet Konstantine Kaznatcheev Matthew Vescovi Yifan Dai Shengyi Li Mourad Idir 《Journal of synchrotron radiation》2016,23(5):1087-1090
Surface slope profile is widely used in the metrology of grazing‐incidence reflective optics instead of surface height profile. Nevertheless, the theoretical and experimental model currently used in deterministic optical figuring processes is based on surface height, not on surface slope. This means that the raw slope profile data from metrology need to be converted to height profile to perform the current height‐based figuring processes. The inevitable measurement noise in the raw slope data will introduce significant cumulative error in the resultant height profiles. As a consequence, this conversion will degrade the determinism of the figuring processes, and will have an impact on the ultimate surface figuring results. To overcome this problem, an innovative figuring model is proposed, which directly uses the raw slope profile data instead of the usual height data as input for the deterministic process. In this paper, first the influence of the measurement noise on the resultant height profile is analyzed, and then a new model is presented; finally a demonstration experiment is carried out using a one‐dimensional ion beam figuring process to demonstrate the validity of our approach. 相似文献
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Summary 3-(2-Furyl) 2-propene aldoxime (FAOH) and 3-(5-methyl 2-furyl) 2-propene aldoxime (M5FAOH) react, in stoichiometric amounts, with 3d divalent metal halides MX2(M=Mn, Co, Ni, Cu and Zh; X=Cl or Br) to givetrans-octahedral complexes, except the ZnCl2 derivative with FAOH which is tetrahedral. These ligands are bidentate in [ML2X2] species (L=FAOH or M5FAOH) through the cyclic oxygen atom and the oxime nitrogen, and are monodentate for [ML4X2] complexes and [ZnCl2(FAOH)2] through the N-oxime atom. The structures were established by analytical and spectroscopic data. 相似文献
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Ali Ourari Kamel Ouari Wahiba Moumeni Lakhdar Sibous Gilles M. Bouet Mustayeen A. Khan 《Transition Metal Chemistry》2006,31(2):169-175
Salicylaldehyde or 5-bromosalicylaldehyde reacted with 2,3-diaminophenol in absolute EtOH in a 2:1 molar ratio to give new
unsymmetrical Schiff bases (H2L). The bases were used as ligands to coordinate Mn(III), Ni(II) and Cu(II) chlorides leading to [MnIIIClL] · EtOH and [MIIL] or [MIIL] · 2H2O (M = Ni or Cu) complexes. Their structures were determined using mass spectroscopy, IR, u.v.–vis and 1H-n.m.r. The cyclic voltammetry in acetonitrile showed irreversible waves for both ligands. Under the same experimental conditions,
the complexes exhibited mainly the non-reversible reduction of the Ni(II) or Cu(II) ion to Ni(0) or Cu(0), while the reduction
of Mn(III) to Mn(II) was found to be a quite reversible phenomenon. 相似文献
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Summary Following our investigations into the complexing properties of 5-substituted 2-furfuraldoximes, we describe here the first complexes obtained from 5-nitro-2-furfuraldoxime (5-NO2-FDH or L) and 3d element dihalides, formulated as [ML2X2], [ML3X2] and [ML4X2] (M = Co, Ni or Cu; X = Cl or Br). The structures are discussed on the basis of analytical, i.r. spectral data and thermal analysis. 相似文献