Efficient cyclopropanation of C₆₀ starting from malonates

Abstract

The direct treatment of C₆₀ with malonates in the presence of CBr₄ and diazabicyclo[5.4.0]undec-7-ene (DBU) leads to an efficient conversion to methanofullerenes, which is demonstrated with the syntheses of monoadducts and highly symmetric hexaadducts in good yields.

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