Chemical Functionalization of Scandium Metallofullerene

Abstract

Endohedral metallofullerenes have attracted special interest, because of the unique properties unexpected for empty fullerenes. In particular, exohedrally derivatized scandium metallofullerenes are very interesting for their potential usefulness as novel materials. One of the most important developments in fullerene chemistry in recent years is the design of Sc3N@C80 derivatives since Sc3N@C80 can be isolated in a remarkably high yield. Here we report the full characterization of the bis-silylated Sc3N@C80. Meanwhile, Sc3C82 is the first endohedral metallofullerene encapsulated three metal atoms. EPR spectrum of Sc3C82 suggests the geometrical equivalency of the three scandium atoms. Surprisingly, we disclosed the molecular structure of Sc3C2@C80 (not Sc3@C82) by 13C NMR spectroscopy and X-ray single-crystal structure analysis. Sc3C2@C80 has the largest endohedral cluster (Sc3C2) encapsulated in an Ih-symmetric C80 cage appears to be the most interesting.