The reaction of copper(II) and 2-hydrazino-2-imidazoline leading to the in situ formation of bisimidazoline (biz). Crystal structure and vibrational spectroscopy of mixed-valence [Cu(biz)2][Cu2Br4] complex

The “in situ” oxidation of 2-hydrazino-2-imidazoline leading to the formation of the Cu(II) complex cation with 2,2′-bi-2-imidazoline is reported. The X-ray analysis monitored the [Cu2Br4]2− as the counter ion. The structures and vibrational spectra of both ions have been reproduced in the DFT calculations. The latter theoretical results have been used for the interpretation of the observed IR and Raman spectra.