Endohedral Fullerene Derivatives: Tether-Directed Functionalizations and Regioisomer Preferences

Addition reactions have been performed (carbene and addition-elimination, Bingel) on Sc₃N@C_2nto determine the preferred mono- as well as multiple addition positions both experimentally and via computations. It has been observed that carbene additions lead to many more isomers than the corresponding addition-elimination reactions of malonates (Bingel reaction), which lead to a rather small number of regioisomers. Theory predicts well the Bingel adducts that are observed experimentally and provides a kinetic rationale for the observations.

Tethered bis-additions have also been explored, especially on Lu₃N@C₈₀, and the results indicate very regioselective bis-additions, with only one bis-regioisomer observed in many cases for bis-carbene additions.

These and other results will be presented and discussed within the context of single and multiple functionalization of endohedral fullerene compounds and how the properties of the products can be controlled via functionalization.