Switch of electronic reactivity in fullerene C₆₀: Activation of three trans-4 positions via temporary saturation of the cis-1 positions

(Chemical Equation Presented) The regioselective functionalization of C₆₀ with a trans-4,trans-4,trans-4 trisaddition pattern is not feasible directly. We have found an indirect approach taking advantage of the modified electronic reactivity of cis-1 bisadducts. The cis-1 addition pattern electronically activates three trans-4 C=C bonds on the opposite hemisphere of C₆₀, allowing further highly regioselective additions at these positions. Thermal removal of the cis-1 blocking unit results in a trans-4,trans-4,trans-4 trisadduct with C_3v symmetry.