Bis[3-tert-butyl-5-(N-oxy-tert-butylamino)phenyl] nitroxide in a quartet ground state: a prototype for persistent high-spin poly[(oxyimino)-1,3-phenylenes]
摘要:
The title trinitroxide 4 was synthesized via the bis[m-(hydroxyamino)phenyl] nitroxides 9 and 10. The ESR spectra obtained in a toluene glass at 4.2 K was consistent with 4 in a quartet state with the zfs parameter \D\/hv of 0.0087 cm-1. The quartet state was shown to be the ground state by the magnetic measurement of its microcrystalline sample on a Faraday balance. The maximum of the effective moment was 3.53-mu-B at ca. 140 K. The Weiss constant and the energy gap between the lowest excited doublet and the ground quartet states were estimated to be -19 and +240 K, repsectively.