Jean-Pierre JOLY - Academia.edu (original) (raw)
Papers by Jean-Pierre JOLY
CCDC 853231: Experimental Crystal Structure Determination
Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, ... more Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, Nathalie Parizel, Katalin Selmeczi, Jean-Pierre Joly|2014|New J.Chem.|38|419|doi:10.1039/C3NJ00570D
CCDC 851239: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 851238: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 851236: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 853231: Experimental Crystal Structure Determination
Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, ... more Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, Nathalie Parizel, Katalin Selmeczi, Jean-Pierre Joly|2014|New J.Chem.|38|419|doi:10.1039/C3NJ00570D
Journal of Coordination Chemistry, 2018
Two copper(II) complexes with tetradentate 1,4-disubstituted-1,2,3-triazole ligands, [CuL(MeCN)](... more Two copper(II) complexes with tetradentate 1,4-disubstituted-1,2,3-triazole ligands, [CuL(MeCN)](ClO 4) 2 (1) and [CuL'](ClO 4) 2 (2), have been prepared and characterized by different techniques, including X-ray structure determination, spectroscopic and electrochemical measurements, as reported elsewhere. Herein, we report the interactions of these complexes, and corresponding free ligands, with human serum albumin (HSA) verifying their relative thermodynamic stability and differences in binding to this protein. Interactions with HSA were verified by CD measurements monitored at 564 nm, up to stoichiometric ratio 2:1 [Complex]:[protein], according to competitive equilibria involving the insertion of copper at the selective N-terminal metal binding site in HSA, and additionally at a secondary non-selective site. Further interactions of these complexes with L-tryptophan residues, and probable supplementary site(s) for the binding, were followed by fluorescence measurements. Analogous experiments with the free L and L' indicated much weaker interactions. Protein oxidation damage was observed for both complexes, monitored by carbonyl groups formation in the presence of H 2 O 2 , probably with the participation of reactive oxygen species (ROS). DFT calculations exhibit metal-ligand binding interaction energies similar to [Cu(HSA-N terminal)] + , and reinforced the experimental results, showing clearly that such triazole ligands are competitive toward copper(II) in biological medium.
Click synthesis of symmetric bis-triazol ligands and full characterisation of their copper(ii)-complexes
New Journal of Chemistry, 2014
ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand... more ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand) and two commercial N,N′-dimethyl-alkyl diamines (acyclic ligands) via the Cu(I)-catalyzed Huisgen dipolar cycloaddition. All C2-symmetric isolated ligands readily formed stable crystalline 1:1-copper(II) complexes with cupric perchlorate. Their structural, electrochemical and physico-chemical properties were fully investigated with the help of X-ray diffraction, cyclic voltammetry, FT-IR, UV-visible, and electron paramagnetic resonance (EPR) spectroscopies. Planar – or nearly planar – arrangement of the two N3-triazole nitrogens and the two tertiary amine pivot nitrogens was found in one single four-coordinated species, in four five-coordinated species, and three six-coordinated species, with one or two solvent molecule(s), or two oxygen atoms of the crown ether, occupying the axial position(s) in the solid sate. The electron-donating or electron-withdrawing effect of the N1-substituent on the triazol was found to influence the Cu(II)/Cu(I) redox potential of all studied complexes in DMF. The EPR-spectrum of cyclic complexes in frozen DMF at 100 K exhibited two mononuclear species, one of them likely promoting the formation of dinuclear species as a minor component, whereas most acyclic complex spectra were quite similar.
Click synthesis of symmetric bis-triazol ligands and full characterisation of their copper(ii)-complexes
New J. Chem., 2014
ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand... more ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand) and two commercial N,N′-dimethyl-alkyl diamines (acyclic ligands) via the Cu(I)-catalyzed Huisgen dipolar cycloaddition. All C2-symmetric isolated ligands readily formed stable crystalline 1:1-copper(II) complexes with cupric perchlorate. Their structural, electrochemical and physico-chemical properties were fully investigated with the help of X-ray diffraction, cyclic voltammetry, FT-IR, UV-visible, and electron paramagnetic resonance (EPR) spectroscopies. Planar – or nearly planar – arrangement of the two N3-triazole nitrogens and the two tertiary amine pivot nitrogens was found in one single four-coordinated species, in four five-coordinated species, and three six-coordinated species, with one or two solvent molecule(s), or two oxygen atoms of the crown ether, occupying the axial position(s) in the solid sate. The electron-donating or electron-withdrawing effect of the N1-substituent on the triazol was found to influence the Cu(II)/Cu(I) redox potential of all studied complexes in DMF. The EPR-spectrum of cyclic complexes in frozen DMF at 100 K exhibited two mononuclear species, one of them likely promoting the formation of dinuclear species as a minor component, whereas most acyclic complex spectra were quite similar.
New J. Chem., 2016
Interlocked [2]rotaxanes were built from bis-cyclodextrinyl-bis lariats (CD-Ls) and bis-aryl sulf... more Interlocked [2]rotaxanes were built from bis-cyclodextrinyl-bis lariats (CD-Ls) and bis-aryl sulfonates by a spontaneous dual cation/anion self-assembling process. Original CD-L's have been synthesized in high yield by a one step “click” or Staudinger–Aza-Wittig (SAW) coupling reaction.
The interaction of an amphiphile crown ether with divalent metal ions. An electrochemical, Langmuir film, and molecular modeling study
Thin Solid Films, 2019
Abstract A new crown ether bearing two hydrophobic lateral chains was synthesized and its complex... more Abstract A new crown ether bearing two hydrophobic lateral chains was synthesized and its complexation properties toward divalent metal ions were studied experimentally and theoretically in water and in non-aqueous environment. Electrochemistry and Langmuir film technique were used to evaluate the stability of complexes formed by the ligand with Cu(II), Zn(II) or Ni(II). Molecular modeling allowed unveiling the structure of the complexes. The results obtained show that all three cations form complexes with the crown ether. However, the stability of the complexes is different depending on the cation and on the environment in which they are formed. This observation suggests that cation complexation can be controlled by adjusting solvent properties; it can be useful in view of possible technological and/or medical applications.
ChemInform Abstract: Synthesis and Complexation Behavior of Some Crown Ethers Derived from D-Hexopyranosides and D-Mannitol Towards Racemic Phenylglycine Salts
ChemInform, 2010
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Tetrahedron: Asymmetry, 2001
Two chiral crown ethers derived from methyl b-D-galactopyranoside are examined as chiral NMR disc... more Two chiral crown ethers derived from methyl b-D-galactopyranoside are examined as chiral NMR discriminating agents for protonated primary amines, amino alcohols, and amino acids. In combination, the solubility and use of the two crown ethers span a range of common NMR solvents including chloroform, acetonitrile, and methanol, which are compatible with the solubilities of various protonated amines. Enantiomeric discrimination is observed in the spectra of most substrates in the presence of the crown ethers. In several cases, the enantiomeric discrimination is larger than observed with previously reported chiral crown ethers. The crown ether V contains a b-diol unit capable of forming a chelate bond with lanthanide(III) ions. Adding ytterbium(III)nitrate to NMR samples in acetonitrile containing V causes substantial enhancements in the enantiodiscrimination in the spectra of several substrates.
Tetrahedron Letters, 1989
Micellar extraction of amino acids using chiral hydrophobic selectors. A comparison with chromatographic procedures
Journal of the Chemical Society, Perkin Transactions 2, 2001
In this work we study the micellar extraction of two amino acids, namely tryptophan and tyrosine,... more In this work we study the micellar extraction of two amino acids, namely tryptophan and tyrosine, using Nn-dodecyl-L-proline (1) and trans-Nn-dodecyl-4-hydroxy-L-proline (2) as hydrophobic chiral selectors with copper (II) ions. In the first part of our study the ...
trans-Fused crown ethers from 2,5-O-methylene-D-mannitol: synthesis, X-ray diffraction structure and full nuclear magnetic resonance spectroscopic data of 1,6-diazido-1,6-dideoxy-2,5-O-methylene-3,4-O-naphthalene-2,3-diylbis(oxyethyleneoxyethylene)-D-mannitol and 3,4-di-O-acetyl-1,6-diazido-1,6-d...
Journal of the Chemical Society, Perkin Transactions 1, 1995
Acta crystallographica. Section C, Crystal structure communications, 2009
The structural model for the title compound, C(16)H(12)N(2)O(2), was refined using a multipolar a... more The structural model for the title compound, C(16)H(12)N(2)O(2), was refined using a multipolar atom model transferred from an experimental electron-density database. The refinement showed some improvements of crystallographic statistical indices when compared with a conventional spherical neutral-atom refinement. The title compound adopts a half-chair conformation. The amide N atom lies almost in the plane defined by the three neighbouring C atoms. In the crystal structure, molecules are linked by weak intermolecular C-H...O and C-H...pi hydrogen bonds.
Acta crystallographica. Section C, Crystal structure communications, 2008
The crystal structure of the title compound, C18H23NO2, was determined using the experimental lib... more The crystal structure of the title compound, C18H23NO2, was determined using the experimental library multipolar atom model. The refinement showed a significant improvement of crystallographic statistical indices when compared with a conventional spherical neutral atom refinement.
Evolution of the coordination-sphere symmetry in copper(II), Nickel(II), and Zinc(II) complexes with N,N'-double-armed diaza-crown ethers: Experimental and theoretical approaches
ABSTRACT N,N′-Bis(triazolyl)diaza[18]crown-6 and corresponding diaza[15]crown-5 ethers were synth... more ABSTRACT N,N′-Bis(triazolyl)diaza[18]crown-6 and corresponding diaza[15]crown-5 ethers were synthesized by means of click chemistry. The interaction of these ligands with NiII, CuII, and ZnII cations were studied by UV/Vis and 1H and 13C NMR spectroscopy. The solid-state structure of NiII and ZnII complexes formed by the diaza[18]crown-6 ligand were determined by means of X-ray crystallography. The NiII complex is centrosymmetric; the geometry around the metal ion is slightly distorted octahedral whereby the equatorial sites were occupied by four N atoms, and the axial positions by two O atoms that come from the crown moiety. For the ZnII–diaza[18]crown-6 complex, an irregular octahedral coordination was observed whereby the metal ion is asymmetrically placed in the macrocyclic cavity. The equatorial plane is occupied by two N and two O atoms of the crown moiety, and two N atoms of the triazolyl motifs on the pendant arms occupy the axial positions. The diamagnetic character of the ZnII ion allows its structural study in solution by NMR spectroscopy. A dynamic behavior was observed at room temperature, which corresponds to the displacement of the ZnII ion between the bond end and the nonbond end of the macrocycle. This movement results in an S4-symmetrical structure in solution. Quantum chemical calculations at the DFT level have allowed us to interpret the experimental results observed in the solid state for the symmetry of the complexes in terms of covalent and noncovalent interactions, which favor the centrosymmetric and irregular octahedral coordination modes, respectively. Only the structure of the CuII complex with N,N′-bis(triazolyl)diaza[15]crown-5 ligand has been investigated in the solid state, for which a pentagonal bipyramidal coordination sphere was observed. This coordination geometry was confirmed in solution in MeCN by UV/Vis spectroscopy, and also for the ZnII complex by NMR spectroscopy. In the case of the NiII complex, a structural modification was suggested in solution in MeCN based on the UV/Vis spectrum. The rearrangement of heptadentate coordination to hexadentate is proposed.
CCDC 853231: Experimental Crystal Structure Determination
Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, ... more Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, Nathalie Parizel, Katalin Selmeczi, Jean-Pierre Joly|2014|New J.Chem.|38|419|doi:10.1039/C3NJ00570D
CCDC 851239: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 851238: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 851236: Experimental Crystal Structure Determination
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 853231: Experimental Crystal Structure Determination
Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, ... more Related Article: Zakia Benkhellat, Mustapha Allali, Marc Beley, Emmanuel Wenger, Maxime Bernard, Nathalie Parizel, Katalin Selmeczi, Jean-Pierre Joly|2014|New J.Chem.|38|419|doi:10.1039/C3NJ00570D
Journal of Coordination Chemistry, 2018
Two copper(II) complexes with tetradentate 1,4-disubstituted-1,2,3-triazole ligands, [CuL(MeCN)](... more Two copper(II) complexes with tetradentate 1,4-disubstituted-1,2,3-triazole ligands, [CuL(MeCN)](ClO 4) 2 (1) and [CuL'](ClO 4) 2 (2), have been prepared and characterized by different techniques, including X-ray structure determination, spectroscopic and electrochemical measurements, as reported elsewhere. Herein, we report the interactions of these complexes, and corresponding free ligands, with human serum albumin (HSA) verifying their relative thermodynamic stability and differences in binding to this protein. Interactions with HSA were verified by CD measurements monitored at 564 nm, up to stoichiometric ratio 2:1 [Complex]:[protein], according to competitive equilibria involving the insertion of copper at the selective N-terminal metal binding site in HSA, and additionally at a secondary non-selective site. Further interactions of these complexes with L-tryptophan residues, and probable supplementary site(s) for the binding, were followed by fluorescence measurements. Analogous experiments with the free L and L' indicated much weaker interactions. Protein oxidation damage was observed for both complexes, monitored by carbonyl groups formation in the presence of H 2 O 2 , probably with the participation of reactive oxygen species (ROS). DFT calculations exhibit metal-ligand binding interaction energies similar to [Cu(HSA-N terminal)] + , and reinforced the experimental results, showing clearly that such triazole ligands are competitive toward copper(II) in biological medium.
Click synthesis of symmetric bis-triazol ligands and full characterisation of their copper(ii)-complexes
New Journal of Chemistry, 2014
ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand... more ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand) and two commercial N,N′-dimethyl-alkyl diamines (acyclic ligands) via the Cu(I)-catalyzed Huisgen dipolar cycloaddition. All C2-symmetric isolated ligands readily formed stable crystalline 1:1-copper(II) complexes with cupric perchlorate. Their structural, electrochemical and physico-chemical properties were fully investigated with the help of X-ray diffraction, cyclic voltammetry, FT-IR, UV-visible, and electron paramagnetic resonance (EPR) spectroscopies. Planar – or nearly planar – arrangement of the two N3-triazole nitrogens and the two tertiary amine pivot nitrogens was found in one single four-coordinated species, in four five-coordinated species, and three six-coordinated species, with one or two solvent molecule(s), or two oxygen atoms of the crown ether, occupying the axial position(s) in the solid sate. The electron-donating or electron-withdrawing effect of the N1-substituent on the triazol was found to influence the Cu(II)/Cu(I) redox potential of all studied complexes in DMF. The EPR-spectrum of cyclic complexes in frozen DMF at 100 K exhibited two mononuclear species, one of them likely promoting the formation of dinuclear species as a minor component, whereas most acyclic complex spectra were quite similar.
Click synthesis of symmetric bis-triazol ligands and full characterisation of their copper(ii)-complexes
New J. Chem., 2014
ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand... more ABSTRACT Eight novel ligands were prepared from a known symmetric diaza-18-crown-6 (cyclic ligand) and two commercial N,N′-dimethyl-alkyl diamines (acyclic ligands) via the Cu(I)-catalyzed Huisgen dipolar cycloaddition. All C2-symmetric isolated ligands readily formed stable crystalline 1:1-copper(II) complexes with cupric perchlorate. Their structural, electrochemical and physico-chemical properties were fully investigated with the help of X-ray diffraction, cyclic voltammetry, FT-IR, UV-visible, and electron paramagnetic resonance (EPR) spectroscopies. Planar – or nearly planar – arrangement of the two N3-triazole nitrogens and the two tertiary amine pivot nitrogens was found in one single four-coordinated species, in four five-coordinated species, and three six-coordinated species, with one or two solvent molecule(s), or two oxygen atoms of the crown ether, occupying the axial position(s) in the solid sate. The electron-donating or electron-withdrawing effect of the N1-substituent on the triazol was found to influence the Cu(II)/Cu(I) redox potential of all studied complexes in DMF. The EPR-spectrum of cyclic complexes in frozen DMF at 100 K exhibited two mononuclear species, one of them likely promoting the formation of dinuclear species as a minor component, whereas most acyclic complex spectra were quite similar.
New J. Chem., 2016
Interlocked [2]rotaxanes were built from bis-cyclodextrinyl-bis lariats (CD-Ls) and bis-aryl sulf... more Interlocked [2]rotaxanes were built from bis-cyclodextrinyl-bis lariats (CD-Ls) and bis-aryl sulfonates by a spontaneous dual cation/anion self-assembling process. Original CD-L's have been synthesized in high yield by a one step “click” or Staudinger–Aza-Wittig (SAW) coupling reaction.
The interaction of an amphiphile crown ether with divalent metal ions. An electrochemical, Langmuir film, and molecular modeling study
Thin Solid Films, 2019
Abstract A new crown ether bearing two hydrophobic lateral chains was synthesized and its complex... more Abstract A new crown ether bearing two hydrophobic lateral chains was synthesized and its complexation properties toward divalent metal ions were studied experimentally and theoretically in water and in non-aqueous environment. Electrochemistry and Langmuir film technique were used to evaluate the stability of complexes formed by the ligand with Cu(II), Zn(II) or Ni(II). Molecular modeling allowed unveiling the structure of the complexes. The results obtained show that all three cations form complexes with the crown ether. However, the stability of the complexes is different depending on the cation and on the environment in which they are formed. This observation suggests that cation complexation can be controlled by adjusting solvent properties; it can be useful in view of possible technological and/or medical applications.
ChemInform Abstract: Synthesis and Complexation Behavior of Some Crown Ethers Derived from D-Hexopyranosides and D-Mannitol Towards Racemic Phenylglycine Salts
ChemInform, 2010
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Tetrahedron: Asymmetry, 2001
Two chiral crown ethers derived from methyl b-D-galactopyranoside are examined as chiral NMR disc... more Two chiral crown ethers derived from methyl b-D-galactopyranoside are examined as chiral NMR discriminating agents for protonated primary amines, amino alcohols, and amino acids. In combination, the solubility and use of the two crown ethers span a range of common NMR solvents including chloroform, acetonitrile, and methanol, which are compatible with the solubilities of various protonated amines. Enantiomeric discrimination is observed in the spectra of most substrates in the presence of the crown ethers. In several cases, the enantiomeric discrimination is larger than observed with previously reported chiral crown ethers. The crown ether V contains a b-diol unit capable of forming a chelate bond with lanthanide(III) ions. Adding ytterbium(III)nitrate to NMR samples in acetonitrile containing V causes substantial enhancements in the enantiodiscrimination in the spectra of several substrates.
Tetrahedron Letters, 1989
Micellar extraction of amino acids using chiral hydrophobic selectors. A comparison with chromatographic procedures
Journal of the Chemical Society, Perkin Transactions 2, 2001
In this work we study the micellar extraction of two amino acids, namely tryptophan and tyrosine,... more In this work we study the micellar extraction of two amino acids, namely tryptophan and tyrosine, using Nn-dodecyl-L-proline (1) and trans-Nn-dodecyl-4-hydroxy-L-proline (2) as hydrophobic chiral selectors with copper (II) ions. In the first part of our study the ...
trans-Fused crown ethers from 2,5-O-methylene-D-mannitol: synthesis, X-ray diffraction structure and full nuclear magnetic resonance spectroscopic data of 1,6-diazido-1,6-dideoxy-2,5-O-methylene-3,4-O-naphthalene-2,3-diylbis(oxyethyleneoxyethylene)-D-mannitol and 3,4-di-O-acetyl-1,6-diazido-1,6-d...
Journal of the Chemical Society, Perkin Transactions 1, 1995
Acta crystallographica. Section C, Crystal structure communications, 2009
The structural model for the title compound, C(16)H(12)N(2)O(2), was refined using a multipolar a... more The structural model for the title compound, C(16)H(12)N(2)O(2), was refined using a multipolar atom model transferred from an experimental electron-density database. The refinement showed some improvements of crystallographic statistical indices when compared with a conventional spherical neutral-atom refinement. The title compound adopts a half-chair conformation. The amide N atom lies almost in the plane defined by the three neighbouring C atoms. In the crystal structure, molecules are linked by weak intermolecular C-H...O and C-H...pi hydrogen bonds.
Acta crystallographica. Section C, Crystal structure communications, 2008
The crystal structure of the title compound, C18H23NO2, was determined using the experimental lib... more The crystal structure of the title compound, C18H23NO2, was determined using the experimental library multipolar atom model. The refinement showed a significant improvement of crystallographic statistical indices when compared with a conventional spherical neutral atom refinement.
Evolution of the coordination-sphere symmetry in copper(II), Nickel(II), and Zinc(II) complexes with N,N'-double-armed diaza-crown ethers: Experimental and theoretical approaches
ABSTRACT N,N′-Bis(triazolyl)diaza[18]crown-6 and corresponding diaza[15]crown-5 ethers were synth... more ABSTRACT N,N′-Bis(triazolyl)diaza[18]crown-6 and corresponding diaza[15]crown-5 ethers were synthesized by means of click chemistry. The interaction of these ligands with NiII, CuII, and ZnII cations were studied by UV/Vis and 1H and 13C NMR spectroscopy. The solid-state structure of NiII and ZnII complexes formed by the diaza[18]crown-6 ligand were determined by means of X-ray crystallography. The NiII complex is centrosymmetric; the geometry around the metal ion is slightly distorted octahedral whereby the equatorial sites were occupied by four N atoms, and the axial positions by two O atoms that come from the crown moiety. For the ZnII–diaza[18]crown-6 complex, an irregular octahedral coordination was observed whereby the metal ion is asymmetrically placed in the macrocyclic cavity. The equatorial plane is occupied by two N and two O atoms of the crown moiety, and two N atoms of the triazolyl motifs on the pendant arms occupy the axial positions. The diamagnetic character of the ZnII ion allows its structural study in solution by NMR spectroscopy. A dynamic behavior was observed at room temperature, which corresponds to the displacement of the ZnII ion between the bond end and the nonbond end of the macrocycle. This movement results in an S4-symmetrical structure in solution. Quantum chemical calculations at the DFT level have allowed us to interpret the experimental results observed in the solid state for the symmetry of the complexes in terms of covalent and noncovalent interactions, which favor the centrosymmetric and irregular octahedral coordination modes, respectively. Only the structure of the CuII complex with N,N′-bis(triazolyl)diaza[15]crown-5 ligand has been investigated in the solid state, for which a pentagonal bipyramidal coordination sphere was observed. This coordination geometry was confirmed in solution in MeCN by UV/Vis spectroscopy, and also for the ZnII complex by NMR spectroscopy. In the case of the NiII complex, a structural modification was suggested in solution in MeCN based on the UV/Vis spectrum. The rearrangement of heptadentate coordination to hexadentate is proposed.