Synthesis, characterisation and structure of a strained ring-tilted bis(indenyl)iron complex

Journal article

The new bridged ligand (C9Me6H)2SiMe2 9 has been prepared and used to synthesise the first strained ansa-bridged bis(indenyl)iron complex Fe(η5-C9Me6)2SiMe2 11. The properties of 11 are compared with those of other SiMe2-bridged [1]-ferrocenophanes and with the unbridged analogue Fe(η5-C9Me6H)2 8. UV-vis and 13C NMR data are consistent with a ring-tilted structure for 11; the strain in the molecule is demonstrated by the observation of alcoholysis and hydrolysis products in its FAB mass spectrum. The crystal structure of rac-Fe(η5 - C9Me6)2SiMe2 11a has been determined; the ring tilt angles of 13.0 and 13.8° (for the two independent molecules in the cell) are the lowest so far reported for a silicon-bridged [1]-ferrocenophane, whilst the distortion of the bridgehead atoms from ideal sp2 geometry is reflected in the angles β between the planes of the five-membered indenyl rings and the C-Si bonds of 43.1 and 41.2°. 57Fe Mössbauer spectra of 11a and 8 suggest the presence of Fe-Si interactions in the former compound.

Authors: Alias, F; Barlow, S; Tudor, J; OHare, D; Perry, RT

• Publication status: Published
• Journal: JOURNAL OF ORGANOMETALLIC CHEMISTRY
• Volume: 528
• Issue: 1-2
• Pages: 47-58
• Publication date: 1997-02-01
• DOI: 10.1016/S0022-328X(96)06434-0
• ISSN: 0022-328X
• Language: English
• Keywords: Mossbauer; ansa-bridged; indenyl; iron; metallocene; crystal structure