Total Synthesis of C60

Abstract

More than 30 years have passed since the discovery of C60, yet its appeal has not faded. Just as a mountaineer climbs a mountain because “there is a mountain there, " it is natural for a synthetic chemist to challenge the “total synthesis” of such an exciting and beautiful molecule. Conventionally, two approaches have been investigated through the step-by-step flask reactions; synthesis of carbon cage molecules and the bottom-up approach from the buckybowls, bowl-shaped partial structure of fullerenes. In particular, two pristine frameworks of buckybowl, corannulene and sumanene, have been intensively studied. The first chemical synthesis of C60 was achieved by flash vacuum pyrolysis, thanks to the careful design of a precursor of C60 which should consist of 60 carbons and should be a planar development diagram. Recent progress of metal surface reactions realized the quantitative synthesis of C60 and the related artificial azafullerene, and even the selective growth of SWCNTs with a single chirality on Pt (111) surface. Although the traditional bottom-up synthesis of C60 using the flask reactions has not been achieved, yet the required pieces for the total synthesis of C60 starting from sumanene are finally in place. The total synthesis route to C60 from sumanene by the convergent synthesis concept might be more promising because of the wide variety of the available reactions and derivatives, and the ease of introducing the sp3 carbons at the appropriate positions for the construction of the three-dimensional structure.