ORGANIC FUNCTIONALIZATION OF C_(60) TOWARD THE SYNTHESIS OF ENDOHEDRAL FULLERENE COMPLEXES

摘要

Attempts have been made to reduce the size of the 13-membered-ring orifice of the open-cage fullerene,encapsulating molecular hydrogen in 100%.The sulfur atom present at the rim of the orifice was first oxidized into an SO group by mild MCPBA oxidation without any loss of the incorporated hydrogen.The following visible-ray irradiation was effective in elimination of the SO unit,thus accomplishing the reduction of the 13-membered-ring orifice into a 12-membered-ring,again without loss of incorporated hydrogen.The MALDI TOF MS spectrum of this compound indicated that a peak for H_2@C_(60) can be now observed as a peak with the highest intensity.Release of hydrogen from this open-cage fullerene with a 12-membered-ring orifice,H_2@2,was suppressed into only 20% even under laser irradiation.Compound H_2@2 is considered as an ideal precursor for the synthesis of endohedral C_(60),containing hydrogen.