Synthesis and Characterization of BINOL Based Axially Chiral Nitronyl Nitroxide Radicals

摘要

Four novel axially chiral nitronyl nitroxides derived from S- or R-1,1'-bi-2-naphthol were synthesized and their crystal structures discussed. Circular dichroism spectra of these compounds showed significant Cotton effects between 200 and 400 nm, and also confirmed the optical activity of these enantiomers. The magnetic properties of the two pairs of nitronyl nitroxide radicals were characterized by magnetic susceptibility measurements. The results showed that in these four radicals exist antiferromagnetic interactions in all cases at low temperatures.