The synthesis and electrochemical properties of spiromethanofullerenes 1-6
are described. The syntheses were achieved via the diazomethane route, and
the regioisomeric distribution of bis-adducts 3 was determined by H-1 NMR,
UV-vis, and HPLC analysis. The electrochemistry of these compounds in dichl
oromethane exhibits, besides several reversible reductions, some irreversib
le waves. Reductive electrolysis of 1 and 3-5 in dichloromethane leads to t
he removal of the addend and thus to the formation of C-60 Reductive electr
olysis of 1, 2 and 6 in dichloromethane leads to a different reaction, whic
h we tentatively assign to a reaction with the solvent to form fullerene-CH
2Cl products. Electrolyses in the less reactive solvent THF lead to adduct
removal for 1 and 3-5. Interestingly, significant formation of bis-adducts
from the corresponding monoadducts was observed for 4 and 5. These electroc
hemically induced reactions, namely addend removal, reaction with the solve
nt, and addend transfer are influenced by the structure of the addend and b
y the choice of solvent.