The First Example of a 2-Imido Functionality Bound to a Lanthanide Metal Center: X-ray Crystal Structure and DFT Study of [
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- 作者：John C. Gordon ; Garth R. Giesbrecht ; David L. Clark ; P. Jeffrey Hay ; D. Webster Keogh ; Rinaldo Poli ; Brian L. Scott ; and John G. Watkin
- 刊名：Organometallics
- 出版年：2002
- 出版时间：October 28, 2002
- 年：2002
- 卷：21
- 期：22
- 页码：4726 - 4734
- 全文大小：318K
- 年卷期：v.21,no.22(October 28, 2002)
- ISSN：1520-6041
文摘
Reaction of 3 equiv of 2,6-diisopropylaniline with Sm[N(SiMe3)2]3 affords the dimeric species[Sm(NHAr)3]2 (1). X-ray crystallography illustrates that each metal center in 1 engages inan 
ges/gifchars/eta.gif" BORDER=0 >6-arene interaction with the aryl ring of an amide ligand attached to an adjacentsamarium. IR spectroscopy indicates that the ges/gifchars/pi.gif" BORDER=0 >-arene interactions are maintained in solution.Reaction of 1 with 4 equiv of trimethylaluminum leads to formation of the bis(ges/entities/mgr.gif">2-imido)complex [(ges/entities/mgr.gif">-ArN)Sm(ges/entities/mgr.gif">-NHAr)(ges/entities/mgr.gif">-Me)AlMe2]2 (2). The molecular structure of 2 contains aunique central Sm2N2 core which displays extremely short bridging Sm-N distances of 2.152(8) and 2.271(7) Å, characteristic of an imido complex. Density functional theory (DFT)calculations have been carried out in order to gain a better understanding of the nature ofthe bonding interactions within complex 2 and indicate that the 5d metal acceptor orbitalsplay a significant role in stabilizing ges/gifchars/pi.gif" BORDER=0 >-donation from the imido groups to the samarium centerswithin the Sm2N2 core.