In one application a liquid fullerene is obtained when the pyrrolidone substituent is a 2,4,6-tris(alkyloxy)phenyl group [3] although a small amount of solvent is still possibly present.
Origins
This reaction was derived from the work of Otohiko Tsuge [4] on Azomethine Ylide Chemistry developed in the late 1980s. Tsuge's work was applied to fullerenes by
Maurizio Prato, thus gaining the name.
Metallofullerenes and Carbon Nanotubes
It is known that the Prato reaction is very useful to functionalize endohedral metallofullerenes. Prato reaction on M3N@C80 gives initially [5,6]-adduct (kinetic product), which convert upon heating to the [6,6]-adduct (thermodynamic product).[5] The rate of isomerization is highly dependent on the metal size inside the carbon cage.[6]
This method is also used in the functionalization of single wall nanotubes.[7] When the amino acid is modified with a
glycine chain the resulting nanotubes are soluble in common solvents such
chloroform and
acetone. Another characteristic of the treated nanotubes is their larger aggregate dimensions compared to untreated nanotubes.
In an alternative method a nanotube addition is performed with the
N-oxide of
trimethylamine and
LDA[8] at reflux in
tetrahydrofuran with an efficiency of 1 functional group in 16 nanotube carbon atoms. When the amine also carries an aromatic group such as
pyrene the reaction takes place even at
room temperature because this group preorganizes itself to the nanotube surface prior to reaction by
pi stacking.
^Tsuge, Otohiko; Kanemasa, Shuji (1989). "Recent Advances in Azomethine Ylide Chemistry". Advances in Heterocyclic Chemistry Volume 45. Vol. 45. pp. 231–349.
doi:
10.1016/S0065-2725(08)60332-3.
ISBN9780120206452.
^Maggini, Michele; Scorrano, Gianfranco; Prato, Maurizio (1993). "Addition of azomethine ylides to C60: synthesis, characterization, and functionalization of fullerene pyrrolidines". J. Am. Chem. Soc.115 (21): 9798–9799.
doi:
10.1021/ja00074a056.
^Michinobu T, Nakanishi T, Hill JP, Funahashi M, Ariga K (2006). "Room Temperature Liquid Fullerenes: An Uncommon Morphology of C60 Derivatives". J. Am. Chem. Soc.128 (32): 10384–10385.
doi:
10.1021/ja063866z.
PMID16895401.
^Tsuge, Otohiko; Kanemasa, Shuji (1989). "Recent Advances in Azomethine Ylide Chemistry". Advances in Heterocyclic Chemistry Volume 45. Vol. 45. pp. 231–349.
doi:
10.1016/S0065-2725(08)60332-3.
ISBN9780120206452.
^Cardona, Claudia M.; Elliott, Bevan; Echegoyen, Luis (2006). "Unexpected Chemical and Electrochemical Properties of M3N@C80 (M = Sc, Y, Er)". J. Am. Chem. Soc.128 (19): 6480–6485.
doi:
10.1021/ja061035n.
PMID16683813.