Preparation and characterization of novel DPPH-based diradicals

✍ Scribed by Masatoshi Kozaki; Shogo Nakamura; Kazunobu Sato; Takeji Takui; Takeaki Kamatani; Masaji Oda; Katsumi Tokumaru; Keiji Okada

• Book ID: 104259651
• Publisher: Elsevier Science
• Year: 1998
• Tongue: French
• Weight: 246 KB
• Volume: 39
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(98)01227-1

✦ Synopsis

A series of 1,1'-(2,4-di-X-benzene-l,3-diyl)bis[1-(4-Y-phenyl)-2-picrylhydrazine]s were prepared and oxidized to generate the corresponding bis-DPPlt diradicals. No triplet species was observed for the compounds with X --H in the ESR measurement. Modification of the central benzene ring (X = Me) and Nphenyl group (Y = OMe, Ph, t-Bu) allowed the detection of their triplet diradicals. Especially, the diradical with X = Me, Y = t-Bu was successfully purified, isolated at 0 °C as a purple solid, and was shown to be in a triplet ground state.