Tether-Directed Multiple Functionalization of Fullerene[60]

Chemical functionalization of fullerenes is the first step to investigate their intriguing properties and applications. The versatile functionalization methods have enabled fullerenes to be extensively studied in many fields, and they are found to have uses in medicines, electronics and optoelectronics. The mono-functionalization of C60 is straightforward, however its multiple functionalization is a challenging job for organic chemists. The stepwise multiple additions to C60 yield a mixture of geometric isomers with low yield and low selectivity for respective isomers, and tedious chromatographic separations are required. A general solution to the multiple addition problem is to find a generic linker which can direct the second addition to expected positions on C60 surface, then the third, and so on. Many research groups have developed tether-directed synthetic methodologies to selectively synthesize C60 multiple adducts. The design and synthesis of C60 isomeric multiple adducts using tether-directed approach will be reviewed in this article.