Mixed ligand binuclear alkoxo-bridged copper(II) complexes derived from aminoalcohols and nitrogen ligands

Six binuclear alkoxo-bridged complexes have been obtained and cystallographically characterized. The binuclear species are spontaneously assembled by reacting copper perchlorate with an aminoalcohol (monoethanolamine, Hmea, or propanolamine, Hpa) in the presence of various co-ligands: 4-phenyl-pyridine (4-phpy) 4-amino-pyridine (4-apy) dipyridylamine (dpyam), 2,3-bis(2-pyridyl)pyrazine (dpp). The six new compounds have the following formulas: [Cu(mea)(4-phpy)(ClO4)]2 1, [Cu(pa)(4-phpy)2]2(ClO4)2 2, [Cu(pa)(4-apy)(ClO4)]2 3, [Cu(mea)(dpyam)]2(ClO4)2 4, [Cu(pa)(dpyam)]2(ClO4)2 5, and [Cu(mea)(dpp)]2(ClO4)2·CH3OH 6. Except compound 1, the binuclear entities in crystals 2 – 6 are centrosymmetric, with pentacoordinated copper ions. In compound 1, one copper is pentacoordinated, while the other one is hexacoordinated. The perchlorate ions play different functions (monodentate and bridging in 1, monodentate in 3, uncoordinated in 2, 4, 5 and 6. The magnetic properties of compound 1 have been investigated and reveal a quite strong ferromagnetic coupling between the copper ions (J = + 81.9 cm−1, H = −JS1S2).