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For the preparation of well-defined H2O-soluble C60 polymers, several C60- PEG conjugates were prepared from a C60 biscarboxylic acid derivative and monodisperse NH2- PEGs ( NH2- EG n, n = 4 - 36) via amide conjugation. When the relatively long PEGs ( EG n, n ≥ 12) were employed, the C60- PEG conjugates became completely H2O-soluble by forming micelle-like structure shown by the data of surface tension, DLS, and cryo- TEM. Interestingly, these H2O-soluble C60- PEG conjugates (C60( EG n)2, n = 12 - 36) showed reversible thermoresponse to form larger aggregates ( ca. 1 μm by DLS) at higher temperatures. The temperature for the aggregation was related to the lengths of PEGs attached to C60; 29 °C (C60( EG n)2, n = 12), 51 °C ( n = 20), and 72 °C ( n = 36). This thermoresponse was speculated to occur by dehydration of well-organized PEG chains in the micelle-type structure of monodisperse C60- PEG caused by gauche-to- anti conformational change of PEG anchors. This thermoresponse of well-defined amphiphilic C60- PEG conjugates indicates potential applications in areas such as temperature sensors and thermoresponsive materials. [ABSTRACT FROM AUTHOR]

Photosensitive C70 was used for the catalytic oxidation of benzylamines to the corresponding imines. The advantages of using C70 compared to C60 or other commonly used photosensitizers such as tetraphenylporphyrin (TPP) are (1) faster reaction rates, especially under lower energy of light sources, (2) clean reactions with simple workup without chromatography, and (3) lower catalyst loadings. The reactions were suitable for various benzylamine derivatives. Subsequent nucleophilic additions to the imines were successfully carried out on substituted products. Quenching experiments in the presence of DABCO and benzoquinone implicate the involvement of the singlet oxygen ((1)O2) and the superoxide radical anion (O2(•-)) as important reactive species in the oxidation.