Junpei Fujita, Masakazu Tanaka, H. Suemune
Oct 2, 1996
Citations
0
Influential Citations
51
Citations
Journal
Journal of the American Chemical Society
Abstract
2,4-Dimethoxy-1,3,5-benzenetriyltris(N-tert-butyl nitroxide) (3) was prepared by lithiation of 2,4-dimethoxy-1,3,5-tribromobenzene followed by the reaction with 2-methyl-2-nitrosopropane and subsequent oxidation with Ag2O. The triradical crystallizes in the orthorhombic space group Pnma (no. 62) with four molecules in the unit cell of dimensions a = 18.200(3) A, b = 19.018(3) A, and c = 6.659(5) A. X-ray analysis for an orange plate single crystal of 3 revealed that the three nitroxide radicals in a molecule have large dihedral angles (90° and 79°) between N−O bonds and the benzene ring plane in the all-syn conformation and the distances between them are 5.44 and 5.28 A. An EPR spectrum of triradical 3 in frozen toluene solution showed quartet signals (g = 2.0062, |D/hc| = 0.010, and |E/hc| = 0.0004 cm-1) in addition to the signals at g = 4.019 and 6.035 due to Δms = 2 and 3 transitions, respectively. Temperature dependence of molar susceptibility for a microcrystalline sample obtained by SQUID measuremen...