An Easy Stereo-Specific and Regio-Selective Reaction for the Synthesis of Ester-[70]-Fullerene Derivatives

Medicinal chemistry is one of the many fields where fullerene derivatives have been shown to be active and useful.^[1,2] Wudl and coworkers reported the interactions of [60]-fullerene derivatives with the active site of HIV protease, driven by the lipophilicity of the carbon cage.^[3] Unfortunately, fullerene derivative applications in this field are hindered mainly by their low water-solubility. To date, water-soluble fullerene C₇₀ derivatives have not been extensively investigated. The lack of low symmetry of the C₇₀ cage makes its selective functionalization more challenging than for C₆₀. Therefore, just a few C₇₀ water-soluble derivatives have been reported. ^[4,5] Here we report an efficient stereo-specific and regio-selective reaction for the synthesis of ester-pyrrolidinofullerene derivatives. These compounds are good precursors for the synthesis of their corresponding water-soluble carboxylic acid-pyrrolidinofullerenes.   

Figure 1. Stereo-specific and regio-selective 1,3-dipolar cyclo-addition reaction of ester-[70]-fullerene derivatives.

 

 

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