Copper(II) complexes with new polypodal ligands presenting axial-equatorial phenoxo bridges {2-[(bis(2-pyridylmethyl)-amino)methyl]-4-methylphenol, 2-[(bis(2-pyridylmethyl)-amino)methyl]-4-methyl-6-(methylthio)phenol}: Examples of ferromagnetically coupled bi- and trinuclear copper(II) complexes

Jorge Manzur, Hector Mora, Andrés Vega, Evgenia Spodine, Diego Venegas-Yazigi, Maria Teresa Garland, M. Salah El Fallah, Albert Escuer

Resultado de la investigación: Article

42 Citas (Scopus)

Resumen

Two new ligands, 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methylphenol (HL) and 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methyl-6-(methylthio)phenol (HSL), were synthesized and were used to prepare the trinuclear copper(II) complex {-[CuSL(Cl)]2·Cu}(PF6)2·H 2O (1) and the corresponding binuclear complexes [Cu 2(SL)2](PF6)2 (2) and [Cu 2L2](PF6)2 (3). The crystal structure of 1 shows two different coordination environments: two square base pyramidal centers (Cu1 and Cu1a, related by a C2 axes), acting as ligands of a distorted square planar copper center (Cu2) by means of the sulfur atom of the SCH3 substituent and the bridging phenoxo oxygen atom of the ligand (Cu2-S = 2.294 Å). Compounds 2 and 3 show two equivalent distorted square base pyramidal copper(II) centers, bridged in an axial-equatorial fashion by two phenoxo groups, thus defining an asymmetric Cu2O2 core. A long copper-sulfur distance measured in 2 (2.9261(18) Å) suggests a weak bonding interaction. This interaction induces a torsion angle between the methylthio group and the phenoxo plane resulting in a dihedral angle of 41.4(5)°. A still larger distortion is observed in 1 with a dihedral angle of 74.0(6)°. DFT calculations for 1 gave a ferromagnetic exchange between first neighbors interaction, the calculated J value for this interaction being +11.7 cm-1. In addition, an antiferromagnetic exchange for 1 was obtained for the second neighbor interaction with a J value of -0.05 cm-1. The Bleaney-Bowers equation was used to fit the experimental magnetic susceptibility data for 2 and 3; the best fit was obtained with J values of +3.4 and -16.7 cm-1, respectively. DFT calculations for 2 and 3 confirm the nature and the values of the J constants obtained by the fit of the experimental data. ESR and magnetic studies on the reported compounds show a weak exchange interaction between the copper(II) centers. The low values obtained for the coupling constants can be explained in terms of a poor overlap between the magnetic orbitals, due to the axial-equatorial phenoxo bridging mode observed in these complexes.

Idioma originalEnglish
Páginas (desde-hasta)6924-6932
Número de páginas9
PublicaciónInorganic Chemistry
Volumen46
N.º17
DOI
EstadoPublished - 20 ago 2007

Huella dactilar

phenols
Copper
Ligands
copper
ligands
Dihedral angle
Sulfur
Discrete Fourier transforms
interactions
dihedral angle
sulfur
Atoms
Exchange interactions
Magnetic susceptibility
Torsional stress
Paramagnetic resonance
Crystal structure
torsion
2-((bis(2-pyridylmethyl)amino)methyl)-4-methyl-6-(methylthio)phenol
2-((bis(2-pyridylmethyl)amino)methyl)-4-methylphenol

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Inorganic Chemistry

Citar esto

@article{051d76244c6e462d8f48f2bcf50b197d,
title = "Copper(II) complexes with new polypodal ligands presenting axial-equatorial phenoxo bridges {2-[(bis(2-pyridylmethyl)-amino)methyl]-4-methylphenol, 2-[(bis(2-pyridylmethyl)-amino)methyl]-4-methyl-6-(methylthio)phenol}: Examples of ferromagnetically coupled bi- and trinuclear copper(II) complexes",
abstract = "Two new ligands, 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methylphenol (HL) and 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methyl-6-(methylthio)phenol (HSL), were synthesized and were used to prepare the trinuclear copper(II) complex {-[CuSL(Cl)]2·Cu}(PF6)2·H 2O (1) and the corresponding binuclear complexes [Cu 2(SL)2](PF6)2 (2) and [Cu 2L2](PF6)2 (3). The crystal structure of 1 shows two different coordination environments: two square base pyramidal centers (Cu1 and Cu1a, related by a C2 axes), acting as ligands of a distorted square planar copper center (Cu2) by means of the sulfur atom of the SCH3 substituent and the bridging phenoxo oxygen atom of the ligand (Cu2-S = 2.294 {\AA}). Compounds 2 and 3 show two equivalent distorted square base pyramidal copper(II) centers, bridged in an axial-equatorial fashion by two phenoxo groups, thus defining an asymmetric Cu2O2 core. A long copper-sulfur distance measured in 2 (2.9261(18) {\AA}) suggests a weak bonding interaction. This interaction induces a torsion angle between the methylthio group and the phenoxo plane resulting in a dihedral angle of 41.4(5)°. A still larger distortion is observed in 1 with a dihedral angle of 74.0(6)°. DFT calculations for 1 gave a ferromagnetic exchange between first neighbors interaction, the calculated J value for this interaction being +11.7 cm-1. In addition, an antiferromagnetic exchange for 1 was obtained for the second neighbor interaction with a J value of -0.05 cm-1. The Bleaney-Bowers equation was used to fit the experimental magnetic susceptibility data for 2 and 3; the best fit was obtained with J values of +3.4 and -16.7 cm-1, respectively. DFT calculations for 2 and 3 confirm the nature and the values of the J constants obtained by the fit of the experimental data. ESR and magnetic studies on the reported compounds show a weak exchange interaction between the copper(II) centers. The low values obtained for the coupling constants can be explained in terms of a poor overlap between the magnetic orbitals, due to the axial-equatorial phenoxo bridging mode observed in these complexes.",
author = "Jorge Manzur and Hector Mora and Andr{\'e}s Vega and Evgenia Spodine and Diego Venegas-Yazigi and Garland, {Maria Teresa} and {El Fallah}, {M. Salah} and Albert Escuer",
year = "2007",
month = "8",
day = "20",
doi = "10.1021/ic700544b",
language = "English",
volume = "46",
pages = "6924--6932",
journal = "Inorganic Chemistry",
issn = "0020-1669",
publisher = "American Chemical Society",
number = "17",

}

TY - JOUR

T1 - Copper(II) complexes with new polypodal ligands presenting axial-equatorial phenoxo bridges {2-[(bis(2-pyridylmethyl)-amino)methyl]-4-methylphenol, 2-[(bis(2-pyridylmethyl)-amino)methyl]-4-methyl-6-(methylthio)phenol}

T2 - Examples of ferromagnetically coupled bi- and trinuclear copper(II) complexes

AU - Manzur, Jorge

AU - Mora, Hector

AU - Vega, Andrés

AU - Spodine, Evgenia

AU - Venegas-Yazigi, Diego

AU - Garland, Maria Teresa

AU - El Fallah, M. Salah

AU - Escuer, Albert

PY - 2007/8/20

Y1 - 2007/8/20

N2 - Two new ligands, 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methylphenol (HL) and 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methyl-6-(methylthio)phenol (HSL), were synthesized and were used to prepare the trinuclear copper(II) complex {-[CuSL(Cl)]2·Cu}(PF6)2·H 2O (1) and the corresponding binuclear complexes [Cu 2(SL)2](PF6)2 (2) and [Cu 2L2](PF6)2 (3). The crystal structure of 1 shows two different coordination environments: two square base pyramidal centers (Cu1 and Cu1a, related by a C2 axes), acting as ligands of a distorted square planar copper center (Cu2) by means of the sulfur atom of the SCH3 substituent and the bridging phenoxo oxygen atom of the ligand (Cu2-S = 2.294 Å). Compounds 2 and 3 show two equivalent distorted square base pyramidal copper(II) centers, bridged in an axial-equatorial fashion by two phenoxo groups, thus defining an asymmetric Cu2O2 core. A long copper-sulfur distance measured in 2 (2.9261(18) Å) suggests a weak bonding interaction. This interaction induces a torsion angle between the methylthio group and the phenoxo plane resulting in a dihedral angle of 41.4(5)°. A still larger distortion is observed in 1 with a dihedral angle of 74.0(6)°. DFT calculations for 1 gave a ferromagnetic exchange between first neighbors interaction, the calculated J value for this interaction being +11.7 cm-1. In addition, an antiferromagnetic exchange for 1 was obtained for the second neighbor interaction with a J value of -0.05 cm-1. The Bleaney-Bowers equation was used to fit the experimental magnetic susceptibility data for 2 and 3; the best fit was obtained with J values of +3.4 and -16.7 cm-1, respectively. DFT calculations for 2 and 3 confirm the nature and the values of the J constants obtained by the fit of the experimental data. ESR and magnetic studies on the reported compounds show a weak exchange interaction between the copper(II) centers. The low values obtained for the coupling constants can be explained in terms of a poor overlap between the magnetic orbitals, due to the axial-equatorial phenoxo bridging mode observed in these complexes.

AB - Two new ligands, 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methylphenol (HL) and 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methyl-6-(methylthio)phenol (HSL), were synthesized and were used to prepare the trinuclear copper(II) complex {-[CuSL(Cl)]2·Cu}(PF6)2·H 2O (1) and the corresponding binuclear complexes [Cu 2(SL)2](PF6)2 (2) and [Cu 2L2](PF6)2 (3). The crystal structure of 1 shows two different coordination environments: two square base pyramidal centers (Cu1 and Cu1a, related by a C2 axes), acting as ligands of a distorted square planar copper center (Cu2) by means of the sulfur atom of the SCH3 substituent and the bridging phenoxo oxygen atom of the ligand (Cu2-S = 2.294 Å). Compounds 2 and 3 show two equivalent distorted square base pyramidal copper(II) centers, bridged in an axial-equatorial fashion by two phenoxo groups, thus defining an asymmetric Cu2O2 core. A long copper-sulfur distance measured in 2 (2.9261(18) Å) suggests a weak bonding interaction. This interaction induces a torsion angle between the methylthio group and the phenoxo plane resulting in a dihedral angle of 41.4(5)°. A still larger distortion is observed in 1 with a dihedral angle of 74.0(6)°. DFT calculations for 1 gave a ferromagnetic exchange between first neighbors interaction, the calculated J value for this interaction being +11.7 cm-1. In addition, an antiferromagnetic exchange for 1 was obtained for the second neighbor interaction with a J value of -0.05 cm-1. The Bleaney-Bowers equation was used to fit the experimental magnetic susceptibility data for 2 and 3; the best fit was obtained with J values of +3.4 and -16.7 cm-1, respectively. DFT calculations for 2 and 3 confirm the nature and the values of the J constants obtained by the fit of the experimental data. ESR and magnetic studies on the reported compounds show a weak exchange interaction between the copper(II) centers. The low values obtained for the coupling constants can be explained in terms of a poor overlap between the magnetic orbitals, due to the axial-equatorial phenoxo bridging mode observed in these complexes.

UR - http://www.scopus.com/inward/record.url?scp=34548221841&partnerID=8YFLogxK

U2 - 10.1021/ic700544b

DO - 10.1021/ic700544b

M3 - Article

C2 - 17655221

AN - SCOPUS:34548221841

VL - 46

SP - 6924

EP - 6932

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

IS - 17

ER -