Highly Oxidized Ruthenium Organometallic Compounds. The Synthesis and One-Electron Electrochemical Oxidation of [Cp*RuIVCl2(S2CR)] (Cp* = 
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- 作者：Seah Ling Kuan ; Elaine Phuay Leng Tay ; Weng Kee Leong ; Lai Yoong Goh ; Ching Yeh Lin ; Peter M. W. Gill ; Richard D. Webster
- 刊名：Organometallics
- 出版年：2006
- 出版时间：December 18, 2006
- 年：2006
- 卷：25
- 期：26
- 页码：6134 - 6141
- 全文大小：225K
- 年卷期：v.25,no.26(December 18, 2006)
- ISSN：1520-6041
文摘
[Cp*RuIVCl2(S2CR)] (R = NMe2, NEt2, and OiPr) were synthesized by the reaction of [Cp*RuIIICl2]2with [RC(S)S]2. One-electron electrochemical oxidation of [Cp*RuCl2(S2CR)] produces paramagnetic[Cp*RuCl2(S2CR)]+, which are stable in CH2Cl2 solution for at least several hours at 233 K. EPRexperiments performed at 293 K show isotropic signals (g 
2.035) with clearly defined hyperfine couplingto 99Ru and 101Ru of 25 G and with peak-to-peak line widths of 15 G. At temperatures below 153 K,axial-shaped EPR spectra were obtained with g-values close to 2 (2.050-2.008) and narrow peak-to-peak line widths (15 G). Results from DFT calculations indicate that approximately 70% of the spindensity in [Cp*RuCl2(S2CNMe2)]+ is located on the ruthenium, although there is an increase of only0.06 in the positive charge of the metal ion as a result of the oxidation. The high spin density on Rusupports the assignment of a formally Ru(V) oxidation state, which is unprecedented in organometallicchemistry. Chemical oxidation of Cp*RuIVCl2(S2CNMe2) with NO(PF6) in CH3CN resulted in the isolationof [Cp*RuIV(MeCN)2(S2CNMe2)]+2 (4), while oxidation with [(4-Br-C6H4)3N](SbCl6) in CH2Cl2 resultedin the formation of chloro-bridged dimeric [Cp*RuIVCl(S2CNMe2)]2+2 (5). When 5 is dissolved in CD3CN/CH3CN, it immediately converts to 4. Cyclic voltammetric experiments confirmed that in both solventsthe chemical oxidation process occurred through the [Cp*RuVCl2(S2CNMe2)]+ intermediate.
2.035) with clearly defined hyperfine couplingto 99Ru and 101Ru of 25 G and with peak-to-peak line widths of 15 G. At temperatures below 153 K,axial-shaped EPR spectra were obtained with g-values close to 2 (2.050-2.008) and narrow peak-to-peak line widths (15 G). Results from DFT calculations indicate that approximately 70% of the spindensity in [Cp*RuCl2(S2CNMe2)]+ is located on the ruthenium, although there is an increase of only0.06 in the positive charge of the metal ion as a result of the oxidation. The high spin density on Rusupports the assignment of a formally Ru(V) oxidation state, which is unprecedented in organometallicchemistry. Chemical oxidation of Cp*RuIVCl2(S2CNMe2) with NO(PF6) in CH3CN resulted in the isolationof [Cp*RuIV(MeCN)2(S2CNMe2)]+2 (4), while oxidation with [(4-Br-C6H4)3N](SbCl6) in CH2Cl2 resultedin the formation of chloro-bridged dimeric [Cp*RuIVCl(S2CNMe2)]2+2 (5). When 5 is dissolved in CD3CN/CH3CN, it immediately converts to 4. Cyclic voltammetric experiments confirmed that in both solventsthe chemical oxidation process occurred through the [Cp*RuVCl2(S2CNMe2)]+ intermediate.