Tether-directed bisfunctionalization reactions of c60 and c70.

Four easily isolable regio- and stereoselective bis-adducts of C60 and C70 , as well as a new C70 -dumbbell derivative, have been synthesized by using two different bismalonate tethered moieties. The derivatives that possess relatively long-tethered moieties show highly symmetric addition patterns, as evidenced by spectroscopic measurements, whereas the derivatives possessing the shorter-tethered moiety exhibit interesting addition patterns on C60 and C70 .