The Synthesis and Spectroscopic Study of Novel Binuclear Chromium(III) Complex with Pipemidic Acid

The interaction of Cr(III) with pipemidic acid, Hpipem, afforded the complex [Cr(pipem)(HO)2(H2O)]2 Cr2O3. The new complex has been characterized by elemental analysis, infrared, XRD and EPR spectroscopy. The EPR spectra of the complex have been recorded down to T = 3 K. The temperature dependence of EPR spectrum demonstrates that spectrum originates from septet transitions at a room temperature and from quintet state for lower temperatures for exchange coupled chromium pairs. The dimer characterizes antiferromagnetic interaction with J = -32 cm-1. The monoanion, pipem, exhibits obligation through the carbonyl and carboxylatooxygen atoms. Six-coordinate dimer distorted octahedral configuration has been proposed for [Cr(pipem)(HO)2(H2O)]2.