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Julia Jezierska - One of the best experts on this subject based on the ideXlab platform.
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stabilities and coordination modes of methionine in copper ii mixed ligand complexes with ethylenediamine diethylenetriamine or n n n n n Pentamethyldiethylenetriamine in aqueous solution
Polyhedron, 2008Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract: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 modes in these mixed-ligand complexes are discussed.
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Stabilities and coordination modes of methionine in copper(II) mixed-ligand complexes with ethylenediamine, diethylenetriamine or N, N, N′, N′′, N′′-Pentamethyldiethylenetriamine in aqueous solution
Polyhedron, 2008Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract: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 modes in these mixed-ligand complexes are discussed.
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unexpected formation of the copper ii dinuclear mixed ligand species in the ternary system of n n n n n Pentamethyldiethylenetriamine with methionine or histidinehydroxamic acids in aqueous solution
Polyhedron, 2007Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract:Equilibrium studies of the mixed-ligand complexes of the copper(II) ion with Pentamethyldiethylenetriamine (N,N,N 0 ,N 00 ,N 00 -pentamethyl-[bis(2-aminoethyl)amine], Me5dien) as a primary ligand and methioninehydroxamic acid (2-amino-4-(methylthio)butanehydroxamic acid, Metha) or histidinehydroxamic acid (2-amino-3-(4 0 -imidazolyl)propanehydroxamicacid, Hisha) as a secondary ligand L were performed by potentiometric titration, UV–Vis and EPR spectroscopy. The results show that in these ternary systems the dinuclear [Cu2(Me5dien)L2H� 1] + mixed-ligand species is formed as a predominant one in the basic solution. The monouclear [Cu(Me5dien)L] + species is formed in low concentration. Our spectroscopic results indicate that the geometry of these mixed-ligand five-coordinate complexes is strongly distorted towards trigonal-bipyramidal. � 2007 Elsevier Ltd. All rights reserved.
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Unexpected formation of the copper(II) dinuclear mixed-ligand species in the ternary system of N,N,N′,N″,N″-Pentamethyldiethylenetriamine with methionine- or histidinehydroxamic acids in aqueous solution
Polyhedron, 2007Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract:Equilibrium studies of the mixed-ligand complexes of the copper(II) ion with Pentamethyldiethylenetriamine (N,N,N 0 ,N 00 ,N 00 -pentamethyl-[bis(2-aminoethyl)amine], Me5dien) as a primary ligand and methioninehydroxamic acid (2-amino-4-(methylthio)butanehydroxamic acid, Metha) or histidinehydroxamic acid (2-amino-3-(4 0 -imidazolyl)propanehydroxamicacid, Hisha) as a secondary ligand L were performed by potentiometric titration, UV–Vis and EPR spectroscopy. The results show that in these ternary systems the dinuclear [Cu2(Me5dien)L2H� 1] + mixed-ligand species is formed as a predominant one in the basic solution. The monouclear [Cu(Me5dien)L] + species is formed in low concentration. Our spectroscopic results indicate that the geometry of these mixed-ligand five-coordinate complexes is strongly distorted towards trigonal-bipyramidal. � 2007 Elsevier Ltd. All rights reserved.
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potentiometric and spectroscopic study of mixed ligand copper ii complexes with n n n n n Pentamethyldiethylenetriamine and α or β alaninehydroxamic acids in water solution
Polyhedron, 2002Co-Authors: Danuta Kroczewska, Barbara Kurzak, Katarzyna Bogusz, Julia JezierskaAbstract:Abstract Stabilities of the mixed-ligand complexes of Cu2+ ion with N,N,N′,N″,N″-Pentamethyldiethylenetriamine [N,N,N′,N″,N″-pentamethyl-{bis(2-aminoethyl)amine}, Me5dien] as a primary ligand and α-alaninehydroxamic acid [2-amino-N-hydroxypropanamid, α-Alaha] or β-alaninehydroxamic acid [3-amino-N-hydroxypropanamid, β-Alaha] as a secondary ligand L and their absorption and EPR spectra at various pH values are reported. The visible spectra exhibit a characteristic red shift and a shoulder at lower energies indicating a five-coordinate structure of the formed complexes. The change of the EPR spectral parameters as a function of pH reflects two modes of an equatorial–axial chelation by the aminohydroxamic acid ligand L in the [Cu(Me5dien)(HL)]2+ and [Cu(Me5dien)(L)]+ species.
Colin L Raston - One of the best experts on this subject based on the ideXlab platform.
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Approaching a cluster of aluminium(III) selenide: [Al4Se5(H)2(NMe3)4]
Chemical Communications, 1997Co-Authors: Peter D. Godfrey, Colin L Raston, Brian W. Skelton, Vicki-anne Tolhurst, Allan H. WhiteAbstract:The reaction of trans-[{Me3N(H)Al(µ-Se)}2] with N,N,N′,N″,N″-Pentamethyldiethylenetriamine (pmdeta) in toluene affords the tetranuclear, alane selenide cluster [Al4Se5(H)2(NMe3)4] (structurally authenticated and ab initio modelled), and with PhTeTePh yields a mixed chalcogenide trans-[{Me3N(PhTe)Al(µ-Se)}2].
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structural variations in the organo potassium derivatives of triphenylmethane with pmdta a new modification of ph3ck n n n n n Pentamethyldiethylenetriamine n
Journal of Organometallic Chemistry, 1997Co-Authors: Michael G Gardiner, Colin L Raston, Vicki-anne Tolhurst, Heiko ViebrockAbstract:Abstract The metalation of triphenylmethane (Ph3CH) with potassium metal in toluene and PMDTA (N,N,N′N″,N″-Pentamethyldiethylenetriamine) at 111 °C affords red crystals of [Ph3CK · PMDTA]n (1). X-ray analysis reveals that the single crystal structure of 1 is different to the one shown previously. Here a polymeric zigzag chain instead of a discrete molecule was observed. Crystal data (Mo K α radiation) at −100°C for 1: a = 9.872(2), b = 18.917(4), c = 29.047(6) A , β = 97.63(3)° , monoclinic space group Cc, R = 0.0449 (F2 > 2σ(F2)), wR2 = 0.1420.
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Structural variations in the organo-potassium derivatives of triphenylmethane with PMDTA: a new modification of [Ph3CK · (N,N,N′,N″,N″-Pentamethyldiethylenetriamine)]n
Journal of Organometallic Chemistry, 1997Co-Authors: Michael G Gardiner, Colin L Raston, Vicki-anne Tolhurst, Heiko ViebrockAbstract:Abstract The metalation of triphenylmethane (Ph3CH) with potassium metal in toluene and PMDTA (N,N,N′N″,N″-Pentamethyldiethylenetriamine) at 111 °C affords red crystals of [Ph3CK · PMDTA]n (1). X-ray analysis reveals that the single crystal structure of 1 is different to the one shown previously. Here a polymeric zigzag chain instead of a discrete molecule was observed. Crystal data (Mo K α radiation) at −100°C for 1: a = 9.872(2), b = 18.917(4), c = 29.047(6) A , β = 97.63(3)° , monoclinic space group Cc, R = 0.0449 (F2 > 2σ(F2)), wR2 = 0.1420.
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Authentication of a sodium primary phosphide: Synthesis and crystal structure of [Na{PH(C6H11)}(pmdeta)]2 (pmdeta=N,N,N′,N″,N″-Pentamethyldiethylenetriamine)
Journal of The Chemical Society Chemical Communications, 1995Co-Authors: George A Koutsantonis, Philip C Andrews, Colin L RastonAbstract:The reaction of the primary phosphine PH2(C6H11) with NaBun in the presence of pmdeta gives the first sodium phosphide containing simple organo substituents [Na{PH(C6H11)}(pmdeta)]21(pmdea =N,N,N′,N″,N″-Pentamethyldiethylenetriamine) to be structurally characterised.
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authentication of a sodium primary phosphide synthesis and crystal structure of na ph c6h11 pmdeta 2 pmdeta n n n n n Pentamethyldiethylenetriamine
Journal of The Chemical Society Chemical Communications, 1995Co-Authors: George A Koutsantonis, Philip C Andrews, Colin L RastonAbstract:The reaction of the primary phosphine PH2(C6H11) with NaBun in the presence of pmdeta gives the first sodium phosphide containing simple organo substituents [Na{PH(C6H11)}(pmdeta)]21(pmdea =N,N,N′,N″,N″-Pentamethyldiethylenetriamine) to be structurally characterised.
Barbara Kurzak - One of the best experts on this subject based on the ideXlab platform.
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Review: Solution equilibria of ternary complexes formed from copper(II), aliphatic amines, and bioligands
Journal of Coordination Chemistry, 2014Co-Authors: Anna Kamecka, Barbara KurzakAbstract: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.
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stabilities and coordination modes of methionine in copper ii mixed ligand complexes with ethylenediamine diethylenetriamine or n n n n n Pentamethyldiethylenetriamine in aqueous solution
Polyhedron, 2008Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract: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 modes in these mixed-ligand complexes are discussed.
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Stabilities and coordination modes of methionine in copper(II) mixed-ligand complexes with ethylenediamine, diethylenetriamine or N, N, N′, N′′, N′′-Pentamethyldiethylenetriamine in aqueous solution
Polyhedron, 2008Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract: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 modes in these mixed-ligand complexes are discussed.
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unexpected formation of the copper ii dinuclear mixed ligand species in the ternary system of n n n n n Pentamethyldiethylenetriamine with methionine or histidinehydroxamic acids in aqueous solution
Polyhedron, 2007Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract:Equilibrium studies of the mixed-ligand complexes of the copper(II) ion with Pentamethyldiethylenetriamine (N,N,N 0 ,N 00 ,N 00 -pentamethyl-[bis(2-aminoethyl)amine], Me5dien) as a primary ligand and methioninehydroxamic acid (2-amino-4-(methylthio)butanehydroxamic acid, Metha) or histidinehydroxamic acid (2-amino-3-(4 0 -imidazolyl)propanehydroxamicacid, Hisha) as a secondary ligand L were performed by potentiometric titration, UV–Vis and EPR spectroscopy. The results show that in these ternary systems the dinuclear [Cu2(Me5dien)L2H� 1] + mixed-ligand species is formed as a predominant one in the basic solution. The monouclear [Cu(Me5dien)L] + species is formed in low concentration. Our spectroscopic results indicate that the geometry of these mixed-ligand five-coordinate complexes is strongly distorted towards trigonal-bipyramidal. � 2007 Elsevier Ltd. All rights reserved.
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Unexpected formation of the copper(II) dinuclear mixed-ligand species in the ternary system of N,N,N′,N″,N″-Pentamethyldiethylenetriamine with methionine- or histidinehydroxamic acids in aqueous solution
Polyhedron, 2007Co-Authors: Barbara Kurzak, Anna Kamecka, Katarzyna Bogusz, Julia JezierskaAbstract:Equilibrium studies of the mixed-ligand complexes of the copper(II) ion with Pentamethyldiethylenetriamine (N,N,N 0 ,N 00 ,N 00 -pentamethyl-[bis(2-aminoethyl)amine], Me5dien) as a primary ligand and methioninehydroxamic acid (2-amino-4-(methylthio)butanehydroxamic acid, Metha) or histidinehydroxamic acid (2-amino-3-(4 0 -imidazolyl)propanehydroxamicacid, Hisha) as a secondary ligand L were performed by potentiometric titration, UV–Vis and EPR spectroscopy. The results show that in these ternary systems the dinuclear [Cu2(Me5dien)L2H� 1] + mixed-ligand species is formed as a predominant one in the basic solution. The monouclear [Cu(Me5dien)L] + species is formed in low concentration. Our spectroscopic results indicate that the geometry of these mixed-ligand five-coordinate complexes is strongly distorted towards trigonal-bipyramidal. � 2007 Elsevier Ltd. All rights reserved.
Latifa Negadi - One of the best experts on this subject based on the ideXlab platform.
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Vapour-liquid equilibria, enthalpy of vaporisation, and excess Gibbs energies of binary mixtures of {3,3-diamino-N-methyldipropylamine (DNM) (or N,N,N′,N′′,N′′-Pentamethyldiethylenetriamine (PMDETA)) + water}
The Journal of Chemical Thermodynamics, 2020Co-Authors: Mohammed Ridha Mahi, Zahida Bouzina, Ilham Mokbel, Amina Negadi, C Goutaudier, Jacques Jose, Latifa NegadiAbstract:Abstract The vapour pressures of the pure components 3,3-diamino-N-methyldipropylamine (DNM) and N,N,N′,N′′,N′′-Pentamethyldiethylenetriamine (PMDETA) along with the binary mixtures (DNM + water) and (PMDETA + water) were measured by means of a static apparatus at temperatures between (283 and 363) K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to four order Redlich-Kister equation using the Barker method. The binary system (DNM + water) exhibits negative deviations in GE values calculated from the vapour pressure data for all investigated temperatures and over the whole composition range. The (PMDETA + water) binary mixture shows a sinusoidal shape for GE at 283.15 K
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vapour liquid equilibria enthalpy of vaporisation and excess gibbs energies of binary mixtures of 3 3 diamino n methyldipropylamine dnm or n n n n n Pentamethyldiethylenetriamine pmdeta water
The Journal of Chemical Thermodynamics, 2019Co-Authors: Mohammed Ridha Mahi, Zahida Bouzina, Ilham Mokbel, Amina Negadi, C Goutaudier, Jacques Jose, Latifa NegadiAbstract:Abstract The vapour pressures of the pure components 3,3-diamino-N-methyldipropylamine (DNM) and N,N,N′,N′′,N′′-Pentamethyldiethylenetriamine (PMDETA) along with the binary mixtures (DNM + water) and (PMDETA + water) were measured by means of a static apparatus at temperatures between (283 and 363) K. The data were correlated with the Antoine equation. From these data, excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to four order Redlich-Kister equation using the Barker method. The binary system (DNM + water) exhibits negative deviations in GE values calculated from the vapour pressure data for all investigated temperatures and over the whole composition range. The (PMDETA + water) binary mixture shows a sinusoidal shape for GE at 283.15 K
Heiko Viebrock - One of the best experts on this subject based on the ideXlab platform.
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Structural variations in the organo-potassium derivatives of triphenylmethane with PMDTA: a new modification of [Ph3CK · (N,N,N′,N″,N″-Pentamethyldiethylenetriamine)]n
Journal of Organometallic Chemistry, 1997Co-Authors: Michael G Gardiner, Colin L Raston, Vicki-anne Tolhurst, Heiko ViebrockAbstract:Abstract The metalation of triphenylmethane (Ph3CH) with potassium metal in toluene and PMDTA (N,N,N′N″,N″-Pentamethyldiethylenetriamine) at 111 °C affords red crystals of [Ph3CK · PMDTA]n (1). X-ray analysis reveals that the single crystal structure of 1 is different to the one shown previously. Here a polymeric zigzag chain instead of a discrete molecule was observed. Crystal data (Mo K α radiation) at −100°C for 1: a = 9.872(2), b = 18.917(4), c = 29.047(6) A , β = 97.63(3)° , monoclinic space group Cc, R = 0.0449 (F2 > 2σ(F2)), wR2 = 0.1420.
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structural variations in the organo potassium derivatives of triphenylmethane with pmdta a new modification of ph3ck n n n n n Pentamethyldiethylenetriamine n
Journal of Organometallic Chemistry, 1997Co-Authors: Michael G Gardiner, Colin L Raston, Vicki-anne Tolhurst, Heiko ViebrockAbstract:Abstract The metalation of triphenylmethane (Ph3CH) with potassium metal in toluene and PMDTA (N,N,N′N″,N″-Pentamethyldiethylenetriamine) at 111 °C affords red crystals of [Ph3CK · PMDTA]n (1). X-ray analysis reveals that the single crystal structure of 1 is different to the one shown previously. Here a polymeric zigzag chain instead of a discrete molecule was observed. Crystal data (Mo K α radiation) at −100°C for 1: a = 9.872(2), b = 18.917(4), c = 29.047(6) A , β = 97.63(3)° , monoclinic space group Cc, R = 0.0449 (F2 > 2σ(F2)), wR2 = 0.1420.
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Über Metallalkyl- und -aryl-Verbindungen, 53. Synthese und Struktur von [9,10-Dihydroanthracenylnatrium(tmeda)]n und [9,10-Dihydroanthracenylnatrium(pmdta)] (tmeda = Tetramethylethylendiamin, pmdta = Pentamethyldiethylentriamin)
Chemische Berichte, 1994Co-Authors: Heiko Viebrock, Ulrich Behrens, Erwin WeissAbstract:On Alkyl- and Arylmetall Compounds, 53[11]. - Synthesis and Structure of [9,10-Dihydroanthracenylsodium(tmeda)]n and [9,10-Dihydroanthracenylsodium(pmdta)] (tmeda = tetramethylethylenediamine, pmdta = Pentamethyldiethylenetriamine) The metalation of 9,10-dihydroanthracene with n-butylsodium (nBuNa) in the presence of the N bases Me2-NCH2CH2NMe2 (tmeda) and Me2NCH2CH2N(Me)CH2-CH2NMe2 (pmdta) yields the solvated 9,10-dihydroanthracenylsodium-base adducts 1 and 2, respectively. According to X-ray diffraction studies the tmeda adduct 1 is a linear polymer in the solid state whereas the pmdta adduct 2 is monomeric.
