Diamond Rings or Dumbbells: Controlling the Structureof Poly(ethylene glycol)–Fullerene [60] Adducts by VaryingLinking Chain Length.

Fullerene[60] (C60) and poly(ethylene glycol) (PEG)adducts were prepared via 1,3-dipolar cycloaddition of bis-azido-terminatedlinear PEG (N3-PEG-N3) and C60. Whilelong chain length PEGs (Mn= 1000 and3350 Da) yielded the cyclic diamond ring structures (⊂C60PEG1000⊃and ⊂C60PEG3350⊃), short-chained PEG (Mn= 200 Da) yielded a telechelic dumbbell structure (C60-PEG200-C60). Both dumbbell and diamondring structures were characterized by MALDI-TOF-MS, 1HNMR, FTIR, UV–vis, and elemental analysis (EA). The resultshighlight the structural dependence of the PEG-C60adductson the chain length of the azido-terminated polymer, a factor previouslyneglected. [ABSTRACT FROM AUTHOR]