New methods for the synthesis of transition-metal fullerene complexes*
David M. Thompson**, Jason McLeod, and Michael C. Baird
Department of Chemistry, Queen's University, Kingston,
Ontario K7L 3N6, Canada
Abstract: Buckminsterfullerene, C60, is readily reduced
on exposure to solutions of strongly reducing transition-metal carbonylate
anions to give the radical anion fulleride C60-
and the corresponding highly reactive, 17-electron neutral compounds.
Three secondary reaction paths have been identified, depending on the
nature of the reactants and the reaction conditions. (1) With Na+
and PPN+ salts of [Mn (CO) 5]-, thermal
substitution of a CO on the metal radical by the C60-results in formation
of the anionic, h2-fullerene complex [Mn (C60) (CO) 4]-
. (2) With salts of [Co (CO) 4]-, the thermal reaction
results in formation of a novel transition-metal fulleride NaCoC60
while (3) with Na[CpFe (CO) 2] and [CpM (CO) 3]-
(M = Mo, W) , the 17-electron intermediates couple to form the 18-electron
dimers, [CpFe (CO) 2]2 and [CpM (CO) 3]2.
In contrast, photochemical reactions of C60 with salts of
[Mn (CO) 5]-, [Co (CO) 4]-,
and [CpM (CO) 3]- result in excellent yields of
the complexes [Mn (C60) (CO) 4]- , [Co (C60) (CO) 3]-
and [CpM (C60) (CO) 2]- , respectively;
analogous complexes of C70 may be made similarly. The new
complexes have been characterized crystallographically, by IR, 13C
NMR, and/or Raman spectroscopy and by electrospray mass spectrometry.
* Lecture presented at the XIXth International Conference
on Organometallic Chemistry (XIX ICOMC) , Shanghai, China, 23-28 July
2000. Other presentations are published in this issue, pp. 205-376.
** Corresponding author
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