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Flash photolytic formation of excited triplet states, their consecutive reductive quenching with diazabicyclooctane (DABCO), and pulse radiolytic formation of n-radical anions of various Cm-derivatives have been recorded. The fullerenes were functionalized via single, double, and triple cyclopropylation of CHI with bromomalonic acid diethyl ester. Flash photolytic irradiation at 308 nm of these Cm derivatives in toluene solution yielded triplet excited states which exhibited a strong blue shift of Am= by nearly 100 nm as compared to plain 3Cm. This is rationalized in terms of a gradual destruction of the fullerene's n-system with an increasing number of bis(ethoxycarbony1)methylene groups. The blue shift coincides with a significant slow down for the rate of reductive quenching of the excited triplet states by DABCO, Le., 1.3 x lo6 M-' s-l vs 2.5 x lo9 M-' s-l for the quenching of eq~atorial-(~C~)[C(COOEt)~]~ and 3C60, respectively. The radical-induced reduction of functionalized c 6 0 has been studied in a toluene/acetone/2-propanol mixture by means of timeresolved pulse radiolysis with measurements being conducted in the characteristic near-IR region. An almost linear dependence is obtained between the energy of the most significant IR-n-radical anion band versus the number of bis(ethoxycarbony1)methylene groups at the fullerene core, with the respective A, , , ranging from 1080 nm for Cm'-to 1015 nm for equatorial-(C60'-)[C(COOEt)~]3. A corresponding trend emerges from cyclic voltammetry measurements on the redox potential in toluene/2-propanol, They show a difference of 330 mV between the formation of Cm'-(E112 = -0.55 V vs SCE) and the first reduction of equatorial-Cm-[C(COOEt)2]3 (E112 = -0.86 V vs SCE). It appears that all these physicochemical parameters very sensitively reflect the site and degree of functionalization of C~O .

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