A Solid-State Intramolecular Wittig Reaction Enables Efficient Synthesis of Endofullerenes Including Ne@C60, 3He@C60, and HD@C60

An open-cage fullerene incorporating phosphorous ylid and carbonyl group moieties on the rim of the orifice can be filled with gases (H-2, He, Ne) in the solid state, and the cage opening then contracted in situ by raising the temperature to complete an intramolecular Wittig reaction, trapping the atom or molecule inside. Known transformations complete conversion of the product fullerene to C-60 containing the endohedral species. As well as providing an improved synthesis of large quantities of He-4@C-60, H-2@C-60, and D-2@C-60, the method allows the efficient incorporation of expensive gases such as HD and He-3, to prepare HD@C-60 and He-3@C-60. The method also enables the first synthesis of Ne@C-60 by molecular surgery, and its characterization by crystallography and C-13 NMR spectroscopy.

Automated summary

Researchers have developed a new method to encapsulate gases in fullerenes and trap molecules inside by raising the temperature to complete a reaction, converting the product into C-60 containing endohedral species. This method allows for the synthesis of He-4@C-60, H-2@C-60, and D-2@C-60 in large quantities, as well as the incorporation of expensive gases like HD and He-3 to prepare HD@C-60 and He-3@C-60 efficiently. Additionally, the method enables the synthesis of Ne@C-60 for the first time through molecular surgery, and its characterization using crystallography and C-13 NMR spectroscopy.