Preparation and Magnetic Properties of Metal-Complexes from N-t-Butyl-N-oxidanyl-2-amino-(nitronyl nitroxide)
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- 作者：Takanori Furui ; Shuichi Suzuki ; Masatoshi Kozaki ; Daisuke Shiomi ; Kazunobu Sato ; Takeji Takui ; Keiji Okada ; Evgeny V. Tretyakov ; Svyatoslav E. Tolstikov ; Galina V. Romanenko ; Victor I. Ovcharenko
- 刊名：Inorganic Chemistry
- 出版年：2014
- 出版时间：January 21, 2014
- 年：2014
- 卷：53
- 期：2
- 页码：802-809
- 全文大小：479K
- ISSN：1520-510X
文摘
Metal complexation reactions of N-t-butyl-N-oxidanyl-2-amino(nitronyl nitroxide) diradical (1) with M(hfac)2 (M: Mn or Cu) were investigated. These reactions were found to be very sensitive to the type of metal ion employed. Complex [Mn(hfac)2路1], consisting of Mn(hfac)2 and diradical 1, was readily prepared by mixing the components. However, the reaction of Cu(hfac)2 with 1 or N-t-butyl-N-oxidanyl-2-amino(iminonitroxide) diradical (2) involved the reduction of the diradical to the N-t-butyl-N-oxidanide-2-amino(iminonitroxide) radical anion (3) and finally produced the polymer-chain complex [Cu2(hfac)2路32路Cu(hfac)2]n. The structures of these complexes were elucidated by X-ray analysis, and their magnetic properties were investigated in detail. The temperature dependence of 蠂pT (蠂p: magnetic susceptibility) for [Mn(hfac)2路1] exhibited a strong antiferromagnetic interaction (H = 鈭?JS1路S2, J/kB = 鈭?17 K) between the Mn(II) spin (S = 5/2) and the diradical 1 spin (S = 1). However, the 蠂pT鈥?i>T plots for [Cu2(hfac)2路32路Cu(hfac)2]n indicated the presence of several magnetic interactions: a large ferromagnetic interaction (J/kB = 510 K) between iminonitroxide 3 and the imino-coordinating Cu(II) atom, a moderately large ferromagnetic interaction (J/kB = 58 K) between the iminonitroxide and (iminonitroxide oxygen)-coordinating Cu(hfac)2, and a weak antiferromagnetic interaction (J/kB = 鈭?.4 K) between the two Cu(hfac)-3 moieties within a Cu2O2 square.