Electronic and bonding properties of mixed-ligand copper(II) complexes of N-(2-pyridylethyl)picolinamide (pepa). Molecular structures of [Cu(pepa)(3-methyl-pyridine) (H2O)](ClO4), [Cu(pepa)(4-methylpyridine) (H2O)](ClO4) and [Cu(pepa)(4-methylimidazole) (H2O)](H2O)(ClO4)

摘要: Abstract Mixed-ligand N-(2-pyridylethyl)picolinamidocopper(II) complexes, Cu(pepa)(L)(H2O)n(ClO4) [pepa = N-(2-pyridylethyl)picolinamide anion; L imidazole (n 0), N-methylimidazole 1), 2-methylimidazole 4-methylimidazole (4MImH, n 2), 3-methylpyridine (3Mpy, n= 1 and 4-methylpyridine (4Mpy, 2)], have been synthesized characterized by elemental analyses, electronic, vibrational EPR spectroscopic measurements. Molecular structures of [Cu(pepa)(3Mpy)(H2O)](ClO4) (1), [Cu(pepa)(4Mpy)(H2O)](ClO4) (2) [Cu(pepa)(4MImH)(H2O)(ClO4) (3) determined X-ray diffraction methods. The these complexes are square pyramidal with the pepa a heterocyclic unidentate ligand forming basal plane an H2O molecule on apical position. dihedral angles nucleus CuN4 74.3° for 1, 66.8° 2 77.7° 3. other suggested to be based their data. sequence d orbitals was assigned as dx2−y2 ⪢ dz2 > dyz dxy dxz complexes. significant rise in energy orbital suggests that central amido is strong π-donor.