Synthesis, structure and ferromagnetic properties of a copper(II) coordination polymer with azide and 4-pyridylacrylate

A Cu(II) complex with azide and 4-pyridylacrylic acid (4-Hpya), [Cu-2(4-pya)(2)(N-3)(2)(DMF)(2)] (1) has been synthesized and characterized crystallographically and spectroscopically. This compound consists of binuclear units in which Cu(II) ions are connected through two equatorial-equatorial end-on azido bridges. The Cu(II) dimers are interlinked by 4-pya to generate two-dimensional coordination polymers. Magnetic investigations revealed a relatively strong ferromagnetic interaction through the azide bridges with J = 145 cm(-1), and a weak ferromagnetic interdimer interaction through the long but pi-conjugated 4-pya ligands. The magneto-structural correlations have been discussed in comparison with other Cu(II) dimers with the same bridging motif. (C) 2008 Elsevier B.V. All rights reserved.