1,3-Dipolar cycloaddition reaction of [60]fullerene with thiocarbonyl ylide and synthetic application of the cycloadduct

C60 reacted with a thiocarbonyl ylide generated by thermal sila-Pummerer rearrangement of bis(trimethylsilylmethyl) sulfoxide to give a tetrahydrothiophene-fused derivative. The corresponding sulfoxide was obtained by oxidation with m-CPBA and further converted into α-acetoxyltetrahydrothiophene derivative by usual Pummerer rearrangement. The O,S-acetal-like moiety in this compound was utilized for electrophilic substitution which is favorable for fullerene chemistry, allowing introduction of various functional groups near the fullerene surface.