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SYNTHESIS AND CHARACTERIZATION OF URANYL(VI) AND THORIUM(IV) COMPLEXES WITH PHOSPHINE OXIDES - THE CRYSTAL-STRUCTURE OF UO2(NO3)2(NO2-C6H4PH2PO)2
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NMR EVIDENCE FOR INTERCONVERSION BETWEEN 2 ENANTIOMERIC FORMS OF MACROCYCLIC SCHIFF-BASE LANTHANIDE(III) COMPLEXES THROUGH REVERSIBLE RING CONTRACTION AND EXPANSION
No full textINTERACTION OF 2,4,6-HEPTANETRIONE WITH 1,5-DIAMINO-3-AZAPENTANE AND SIMILAR POLYAMINES - THE CRYSTAL AND MOLECULAR-STRUCTURE OF A NEW HETEROCYCLIC COMPOUND
No full textFunctionalisation of silica gel with cyclic and acyclic Schiff bases and related d- and/or f-metal complexes
No full textTwo different synthetic pathways were devised in order to graft on silica gel organic moieties, containing macroacyclic or macrocyclic compartimental ligands, formed of an inner N(3)O(2), or NO, Schiff base site, able to coordinate d metal ions, and one adjacent 0,0, or 0204 crown ether-like chamber suitable for hosting f ions, in the terminal part. These materials can bind d metal ions into the amine-imine moiety. Their subsequent reaction with varying amounts of gadolinium(III) invariantly gives a system in which two grafted copper complexes coordinate only one gadolinium(III) ion with their oxygen-containing chambers, giving rise to a trinuclear Cu(2)Gd entity
ELECTRON-IMPACT MASS-SPECTRA OF NEW ACYCLIC AND MACROCYCLIC SULFUR-CONTAINING SCHIFF-BASES
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Mononuclear and polynuclear complexes with a side-off compartmental Schiff base
No full textThe compartmental Schiff base H(2)-L, obtained by [2 + 1] condensation of 3-methoxy-2-hydroxybenzaidehyde and 1,5-diamino-3-azapentane, and the related mono- and hetero-polynuclear copper(II), zinc(II) and lanthanum(III) complexes have been prepared and their physico-chemical properties studied by IR, NMR, SEM-EDS and X-ray single crystal diffractometry. In the mononuclear complexes [M(L)] center dot nS (M = Cu(II), Zn(II), S = H(2)O, MeOH), obtained in alcoholic solution by the reaction of the free ligand and the appropriate metal acetate hydrate or nitrate or by [2 + 1] condensation of the formyl- and polyamine-derivatives in the presence of the desired metal salt, [L](2-) coordinates to the metal ion in the diimine form as ascertained by the 1 H NMR spectra of the zinc(II) complex. The hetero-dinuclear complexes have been prepared by the reaction of the copper(H) or zinc(II) mononuclear complex with La(NO(3))(3)center dot 6H(2)O in 1:1 molar ratio. The copper-lanthanum complex is not a true heterodinuclear complex, as it can be described as {[Cu(2)(H(2)L)(2)](2)[La(NO(3))(6)](NO(3))}, while heterodinuclear complexation occurs in {[ZnLa(H-L')(NO(3))(3)(S)](NO(3))) (S = H(2)O or C(2)H(5)OH), where a ring contraction at one imine group takes place, with the formation of a five-membered heterocyclic imidazolidine ring
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