A multifunctional high-spin biradical pyrazolylbipyridine-bisnitronylnitroxide.
[structure: see text] Synthesis and UV-vis, IR, and EPR spectroscopic characterizations, together with X-ray structural analysis, of functional nitronyl- and iminonitroxides attached to pyrazolylbipyridine are described. The exchange interactions between the nitronylnitroxides are found to be stronger than for the iminonitroxides. Although the substitution of a pyridine with the pyrazole ring leads to shorter distances and larger dipolar couplings, the exchange interaction is diminished. While compound 1 forms dimers in the solid state, the terpyridine 3 leads to supramolecular pi-stacking.
Zoppellaro
Giorgio
G
Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128, Mainz, Germany.
Enkelmann
Volker
V
Geies
Ahmed
A
Baumgarten
Martin
M