Prato reaction

The Prato reaction is a particular example of the well-known

Applications

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

Retro-Prato reaction

Just as in other fullerene reactions like the

Other methods have been investigated: by applying heat ^[10] or via a combination of ionic liquid and microwave chemistry.^[11][12]

References