First homoleptic complexes of isocyanoferrocene.

Abstract

Interaction of aminoferrocene with a 65/35 mol % mixture of phenyl formate/phenol followed by subsequent dehydration of the resulting ferrocenylformamide with POCl3 produced a high yield of air- and thermally stable, peach-colored isocyanoferrocene (CNFc). Combining 6 equiv of CNFc with bis(naphthalene)chromium(0) afforded orange-red Cr(CNFc)6, the first homoleptic complex of CNFc. Successive one-electron oxidations of the latter with Ag+ quantitatively produced saddle-brown [Cr(CNFc)6]+ and forest-green [Cr(CNFc)6]2+. The compounds [Cr(CNFc)6]0,1+,2+ are air-, light-, and thermally robust and are remarkable due to the incorporation of seven potentially electroactive transition metal ions within a relatively compact ML6 motif. Their properties demonstrate that the pi-accepting potential of the ferrocenyl substituent, customarily compared to an alkyl group, may have been underestimated. Indeed, the donor/acceptor ratio of the CNFc ligand appears to be similar to those of aryl isocyanides but quite different from those of alkyl isocyanides. Spectroscopic (including multinuclear paramagnetic NMR), magnetic, structural, and electrochemical characteristics of the above substances are discussed. In addition, a DFT analysis of the Frontier molecular orbitals of CNFc is presented.

• Authors: Mikhail V Barybin, Thomas C Holovics, Stephan F Deplazes, Gerald H Lushington, Douglas R Powell, Masaharu Toriyama
• Journal: Journal of the American Chemical Society (J Am Chem Soc) Vol. 124 Issue 46 Pg. 13668-9 (Nov 20 2002) ISSN: 0002-7863 [Print] United States
• PMID: 12431084 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Ferrous Compounds
• Organometallic Compounds
• isocyanoferrocene

Topics

• Crystallography, X-Ray
• Ferrous Compounds (chemical synthesis, chemistry)
• Magnetic Resonance Spectroscopy
• Organometallic Compounds (chemical synthesis, chemistry)