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Synthesis and Properties of Cyclic π-Conjugated Molecules and Their Dication and Monoradical Cation
Runjie Xu1, Yoichiro Kuninobu2,1
1Department of Interdisciplinary Engineering Sciences, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakoen, Kasuga-shi, Fukuoka 816-8580, Japan.
Abstract:
We synthesized cyclic π-conjugated molecules by double Friedel-Crafts reaction of amino group-substituted 1,2-bis(2-phenylethynyl)benzene with Meldrum's acid derivative. The structures of the cyclic π-conjugated molecules were determined by single-crystal X-ray structure analysis. The oxidation of the dimethylamino group-substituted π-conjugated molecule with NOBF4 gave a closed-shell dication that is stable at >210 °C. The monoradical cation of the di(4-methoxyphenyl)amino group-substituted π-conjugated molecule is stable in dichloromethane solution (half-life of nearly 15 days) and shows near-infrared absorption.
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