Interactions of Cationic and Neutral Molybdenum Complexes with -Cyclodextrin Host Molecules
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- 作者：Sé ; rgio Lima ; Isabel S. Gonç ; alves ; Paulo Ribeiro-Claro ; Martyn Pillinger ; André ; D. Lopes ; Paula Ferreira ; José ; J. C. Teixeira-Dias ; Joã ; o Rocha ; and Carlos C. Rom&atil
- 刊名：Organometallics
- 出版年：2001
- 出版时间：May 28, 2001
- 年：2001
- 卷：20
- 期：11
- 页码：2191 - 2197
- 全文大小：103K
- 年卷期：v.20,no.11(May 28, 2001)
- ISSN：1520-6041
文摘
The inclusion compounds formed between 
chars/beta2.gif" BORDER=0 ALIGN="middle">-cyclodextrin (chars/beta2.gif" BORDER=0 ALIGN="middle">-CD) and the tetrafluoroboratesalts [Cp'Mo(chars/eta.gif" BORDER=0 >4-C6H8)(CO)2][BF4] and the neutral derivatives Cp'Mo(chars/eta.gif" BORDER=0 >3-C6H7)(CO)2 [Cp' =Cp (chars/eta.gif" BORDER=0 >5-C5H5), Ind (chars/eta.gif" BORDER=0 >5-C9H7)] were studied by means of elemental analysis, FTIR spectroscopy,thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), and magic-angle spinning(MAS) NMR (13C, 11B). Additional information concerning the possible structure of theinclusion compounds was obtained from ab initio calculations using a two-layer approximation. The cationic and neutral chars/eta.gif" BORDER=0 >5-cyclopentadienyl analogues form stable two-to-one (host-to-guest) channel-type inclusion compounds in a crystalline state. By contrast, the chars/eta.gif" BORDER=0 >5-indenylanalogues form only weak complexes with chars/beta2.gif" BORDER=0 ALIGN="middle">-CD and it is evident that the organometallicguests are easily liberated from the host cavities. The ab initio calculations revealed thatthe steric hindrance arising from the presence of the indenyl ligand is a possible explanationfor the experimentally observed lower stability of these compounds.
chars/beta2.gif" BORDER=0 ALIGN="middle">-cyclodextrin (chars/beta2.gif" BORDER=0 ALIGN="middle">-CD) and the tetrafluoroboratesalts [Cp'Mo(chars/eta.gif" BORDER=0 >4-C6H8)(CO)2][BF4] and the neutral derivatives Cp'Mo(chars/eta.gif" BORDER=0 >3-C6H7)(CO)2 [Cp' =Cp (chars/eta.gif" BORDER=0 >5-C5H5), Ind (chars/eta.gif" BORDER=0 >5-C9H7)] were studied by means of elemental analysis, FTIR spectroscopy,thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), and magic-angle spinning(MAS) NMR (13C, 11B). Additional information concerning the possible structure of theinclusion compounds was obtained from ab initio calculations using a two-layer approximation. The cationic and neutral chars/eta.gif" BORDER=0 >5-cyclopentadienyl analogues form stable two-to-one (host-to-guest) channel-type inclusion compounds in a crystalline state. By contrast, the chars/eta.gif" BORDER=0 >5-indenylanalogues form only weak complexes with chars/beta2.gif" BORDER=0 ALIGN="middle">-CD and it is evident that the organometallicguests are easily liberated from the host cavities. The ab initio calculations revealed thatthe steric hindrance arising from the presence of the indenyl ligand is a possible explanationfor the experimentally observed lower stability of these compounds.