Decamethylferrocene

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Decamethylferrocene
Decamethylferrocene.svg
Identifiers
CAS number 12126-50-0 YesY
Properties
Molecular formula C20H30Fe
Molar mass 326.30 g mol−1
Appearance Yellow crystalline solid[1]
Melting point 291-295 °C[1]
Sublimation conditions 413 K, 5.3 Pa[2]
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Decamethylferrocene is a sandwich compound. In terms of structure and bonding it resembles ferrocene, but with a methyl group on each of the carbons of the Cp rings. It is a yellow crystalline solid that is a weak reductant.

Preparation[edit]

Decamethylferrocene is prepared in the same manner as ferrocene from pentamethylcyclopentadiene. This method can be used to produce other decamethylcyclopentadienyl sandwich compounds.[1]

2 Li(C5Me5) + FeCl2 → Fe(C5Me5)2 + 2 LiCl

The product can be purified by sublimation. FeCp2* has staggered Cp* rings. The average distance between iron and each carbon is approximately 2.050 Å. This structure has been confirmed by X-ray crystallography.[3]

Redox reactions[edit]

Like ferrocene, decamethylferrocene forms a stable cation because Fe(II) is easily oxidized to Fe(III). Because of the electron donating methyl groups on the Cp* groups, decamethylferrocene is more reducing than is ferrocene. In a solution of MeCN the reduction potential for the [FeCp2*]+/0 couple is -0.48 compared to a [FeCp2]0/+ reference (-0.59 V V vs Fc/Fc+ in CH2Cl2).[2] Oxygen is reduced to hydrogen peroxide by decamethylferrocene in acidic solution.[4]

References[edit]

  1. ^ a b c King, R. B., and M. B. Bisnette (1967). "Organometallic Chemistry of the Transition Metals XXI. Some π-pentamethylcyclopentadienyl Derivatives of Various Transition Metals". J. Organomet. Chem. 8 (2): 287–297. doi:10.1016/S0022-328X(00)91042-8. 
  2. ^ a b Connelly, N., and W.E. Geiger (1996). "Chemical Redox Agents for Organometallic Chemistry". Chem. Rev. 96: 877–910. doi:10.1021/cr940053x. PMID 11848774. 
  3. ^ Freyberg, D. J, L. Robbins, K.N. Raymond and J.C. Smart (1979). "Crystal and molecular structures of decamethylmanganocene and decamethylferrocene. Static Jahn-Teller distortion in a metallocene". J. Am. Chem. Soc. 101 (4): 892–897. doi:10.1021/ja00498a017. 
  4. ^ Su, B.; Hatay, I.; Ge, P. Y.; Mendez, M.; Corminboeuf, C.; Samec, Z.; Ersoz, M. and Girault, H. H., "Oxygen and proton reduction by decamethylferrocene in non-aqueous acidic media", Chem. Commun., 2010, volume 46, 2918-2919. doi:10.1039/B926963K