Precursors to Endohedral Metal Fullerene Complexes: Synthesis and X-ray Structure of a Flexible Acetylenic Cyclophane C_(60)H_(18)

摘要

The rational synthesis of stable endohedral metal fnllerene complexes poses a major challenge to current synthetic methodologies. We are particulariy interested in C_(60) endohedral complexes because C_(60) itself has deli vered the most interesting physical properties among the empty fullerenes. While lanthanide endohedral complexes of higher fullerenes (e.g. La @C_(82)) have been available for some time by resistive evaporation methods, analogous C_(60) comixes do not seem to be isolable. Endbhedral complexes of C_(60) with noble gases (e.g. He@C_(60)) have been prepared, by insertion into empty fullerenes under high pressure and temperature. These methods are limited by the choice of guest atom, fullerene size, and very low yields.