Bimetallic Zwitterionic Complexes with an Ambident Stanna-closo-dodecaborate Ligand: [1-{M(CO)5}-2,7,8-(-H)
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- 作者：Torben Gä ; dt ; Klaus Eichele ; Lars Wesemann
- 刊名：Organometallics
- 出版年：2006
- 出版时间：July 31, 2006
- 年：2006
- 卷：25
- 期：16
- 页码：3904 - 3911
- 全文大小：159K
- 年卷期：v.25,no.16(July 31, 2006)
- ISSN：1520-6041
文摘
Starting from FeBr2 the zwitterionic stannaborate complex [1-{Fe(MeCN)2(triphos)}-SnB11H11] (1)could be obtained in a straightforward one-pot synthesis. Via a facile 
1(Sn) to 3(BH) rearrangementreaction 1 can be converted into [2,7,8-(
-H)3-{Fe(triphos)}-SnB11H11] (2). The nucleophilicity of thetin atom in compound 2 is strongly reduced compared to the dianionic parent stannaborate cluster[SnB11H11]2-. Methylation at the tin atom using standard methods is not feasible. Transition metal fragmentscan be coordinated at the tin atom of 2 if reactive species such as M(CO)5(THF) (M = Cr, Mo, W) areemployed. Reaction of these fragments with 2 yields the bimetallic zwitterions [1-{M(CO)5}-2,7,8-(-H)3-{Fe(triphos)}-SnB11H11] (M = Cr, Mo, W) (3, 4, 5), which contain an ambident stannaborate moiety.All new compounds have been characterized using 1H, 11B, 13C, 31P, and 119Sn NMR spectroscopy aswell as 31P and 119Sn MAS NMR experiments. Single-crystal X-ray diffraction analyses have been carriedout for all novel compounds.
1(Sn) to 3(BH) rearrangementreaction 1 can be converted into [2,7,8-(-H)3-{Fe(triphos)}-SnB11H11] (2). The nucleophilicity of thetin atom in compound 2 is strongly reduced compared to the dianionic parent stannaborate cluster[SnB11H11]2-. Methylation at the tin atom using standard methods is not feasible. Transition metal fragmentscan be coordinated at the tin atom of 2 if reactive species such as M(CO)5(THF) (M = Cr, Mo, W) areemployed. Reaction of these fragments with 2 yields the bimetallic zwitterions [1-{M(CO)5}-2,7,8-(-H)3-{Fe(triphos)}-SnB11H11] (M = Cr, Mo, W) (3, 4, 5), which contain an ambident stannaborate moiety.All new compounds have been characterized using 1H, 11B, 13C, 31P, and 119Sn NMR spectroscopy aswell as 31P and 119Sn MAS NMR experiments. Single-crystal X-ray diffraction analyses have been carriedout for all novel compounds.