0000000000172751
AUTHOR
Barbara Kurzak
showing 9 related works from this author
Coordination abilities of N-methyl alkylaminomethane-1,1-diphosphonic acids towards zinc(II), magnesium(II) and calcium(II) metal ions. Equilibrium s…
2017
Abstract Complex-formation abilities of a series of N-methyl alkylaminomethane-1,1-diphosphonic acids (1–7) with a common tertiary nitrogen atom (CH3−N−R) bearing linear or branched alkyl, cycloheptyl or phenylalkyl R substituents towards zinc(II), magnesium(II) and calcium(II) in aqueous solution have been studied by means of pH-potentiometry, ESI-MS spectrometry, 1H NMR and 31P NMR methods. The obtained results indicate that in the all presented systems mononuclear protonated equimolar and bis complexes are formed. In acidic and neutral solution, the formation of the protonated dinuclear species has been confirmed. The comparative analysis of the potentiometric and NMR data reveal that th…
Synthesis of N-methyl alkylaminomethane-1,1-diphosphonic acids and evaluation of their complex-formation abilities towards copper(II)
2015
Abstract A series of N -methyl alkylaminomethane-1,1-diphosphonic acids ( 3a – g ) with a common tertiary nitrogen atom (CH 3 –N–R) bearing linear or branched alkyl, cycloheptyl or phenylalkyl R substituents was synthesized in the reaction of diethylphosphonate with triethyl orthoformate and secondary amine followed by hydrolysis, and by the Eschweiler–Clarke methylation of the alkylaminomethane-1,1-diphosphonic acids with formic acid and formaldehyde. Complex-formation abilities of 3a – g towards copper(II) in solution were studied by means of pH-potentiometry, ESI-MS spectrometry, UV–Vis and EPR methods. Evaluation of stability constants for the Cu(II) complexes of 3a – g has revealed the…
Stabilities and coordination modes of histidine in copper(II) mixed-ligand complexes with ethylenediamine, diethylenetriamine or N,N,N′,N″,N″-pentame…
2008
Abstract Solution equilibrium studies on the Cu(II)–polyamine–methionine ternary systems (polyamine: ethylenediamine (en), diethylenetriamine (dien), N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (Me5dien)) have been performed by pH-potentiometry, UV–Vis spectrophotometry and EPR methods. The obtained results suggest the formation of the mixed-ligand complexes with [Cu(A)(Met)]+ stoichiometry in all studied systems. Our spectroscopic results indicate the tetragonal geometry for [Cu(en)(Met)]+, the geometry slightly deviated from square pyramidal for [Cu(dien)(Met)]+ and strongly deviated from square pyramidal towards trigonal bipyramidal for the [Cu(Me5dien)(Met)]+ species. The coordination …
Stabilities and Coordination Modes of α-Alaninephosphonic Acid in Copper(II) Heteroligand Complexes with Ethylenediamine, Diethylenetriamine or N,N,N…
2011
Solution equilibrium studies on Cu2+–L1–L2 ternary systems have been performed by pH-potentiometry, UV–Vis spectrophotometry and EPR methods (L1 corresponds to polyamines such as ethylenediamine (en), diethylenetriamine (dien), or N,N,N′,N′,N″-pentamethyldiethylenetriamine (Me5dien) and L2 represents 1-aminoethylphosphonic acid (α-alaninephosphonic acid)). The obtained results suggest the formation of heteroligand complexes with [Cu(L1)(α-Ala(P))] stoichiometry in all studied systems. Additionally, in the system with en the [Cu(en)(α-Ala(P))H−1]− species is formed in basic solution. Our spectroscopic results indicate tetragonal geometry for the [Cu(en)(α-Ala(P))] species, geometry slightly …
Coordination properties of some nickel(II) monophosphono dipeptides species in aqueous solution: The role of phosphonic oxygen in complex stabilizati…
2008
Abstract Equilibrium studies on the nickel(II) complexes of oxygen and nitrogen donor ligand (monophosphono dipeptides: 1- (N- l -leucylamino)methylphosphonic acid – Leu-Gly(P), and a thioether sulfur donor ligands (monophosphono dipeptides: 1-N-(glycyloamino)-2-(S-benzylthio)ethanephosphonic acid – Gly-(Bz)Cys(P), d (−) and Gly-(Bz)Cys(P), d (+) were performed by potentiometric titration and NIR–Vis spectroscopy. Additionally, the ligand-field parameters (CFM/AOM) were estimated and discussed in the tetragonal distortion framework. The lowest tetragonal distortion was observed in the case of the [NiHL] species, whereas the strongest in the case of [NiL2] species. In the latter species the …
Review: Solution equilibria of ternary complexes formed from copper(II), aliphatic amines, and bioligands
2014
This review provides a summary of the coordination chemistry of ligands in the ternary system: copper(II)–aliphatic amine–bioligand, where amine = ethylenediamine – En, diethylenetriamine – Dien, or N, N, N′, N″, N″-pentamethyldiethylenetriamine – Me5dien, and bioligand = selected amino acid, aminohydroxamic acid, or aminophosphonic acid, in aqueous solution. We would like to show the specific interactions of copper(II) in ternary systems in the context of complex equilibria chemistry.
NMR, potentiometric and ESI-MS combined studies on the zinc(II) magnesium(II) and calcium(II) complexation by (morpholin-1-yl)methane-1,1-diphosphoni…
2012
Abstract The crystal structures of the two derivatives of aminomethane-1,1-diphosphonic acid with morpholinyl- (1) and thiomorpholinyl- (2) side chains were determined by single crystal X-ray diffraction and discussed with respect to molecular geometry and solid state organization. The protonation equilibria, solution behavior and complex-formation equilibria in solutions of 1 and 2 with the Zn(II), Mg(II) and Ca(II) ions were studied by means of NMR, pH-potentiometry and ESI-MS methods. As the p K ( NH + ) protonation constants of 1 and 2 are high (11.65 and 11.91, respectively) two different approaches were used to evaluate the pH-potentiometric data. The first approach disregarded the pr…
ChemInform Abstract: Review: Solution Equilibria of Ternary Complexes Formed from Copper(II), Aliphatic Amines, and Bioligands
2014
This review provides a summary of the coordination chemistry of ligands in the ternary system: copper(II)–aliphatic amine–bioligand, where amine = ethylenediamine – En, diethylenetriamine – Dien, or N, N, N′, N″, N″-pentamethyldiethylenetriamine – Me5dien, and bioligand = selected amino acid, aminohydroxamic acid, or aminophosphonic acid, in aqueous solution. We would like to show the specific interactions of copper(II) in ternary systems in the context of complex equilibria chemistry.
Coordination abilities of l-glutamic acid γ-monohydroxamic acid towards copper(II) in the absence and presence of some aliphatic amines
2012
Abstract Solution equilibrium studies on the Cu 2+ –(A)–(Glu-γ-ha) ternary systems ((A) = polyamine: ethylenediamine (en), diethylenetriamine (dien), N , N , N ′, N ″, N ″-pentamethyldiethylenetriamine (Me 5 dien); (Glu-γ-ha) = l -glutamic-γ-hydroxamic acid) have been performed by pH-potentiometry, UV–Vis spectrophotometry and EPR methods. The obtained results suggest the formation of the heteroligand complexes with [Cu(A)(Glu-γ-ha)] + stoichiometry in all studied systems. Our spectroscopic results indicate the tetragonal geometry for the [Cu(en)(Glu-γ-ha)] + species in which Glu-γ-ha acts as a tridentate ligand, the geometry slightly deviated from square pyramidal for [Cu(dien)(Glu-γ-ha)]…