A rational chemical synthesis of C60

Notable quantities of C-60, the smallest stable fullerene, have been synthesized in 12 steps from commercially available starting materials by rational chemical methods. A molecular polycyclic aromatic precursor bearing chlorine substituents at key positions forms C-60 when subjected to flash vacuum pyrolysis at 1100degreesC. No other fullerenes are formed as by-products. The methods we have developed for the target-specific synthesis of fullerenes, applied here to a synthesis of C-60, should make possible the directed laboratory preparation of other fullerenes as well, including those not accessible by graphite vaporization.