Photosensitivity is one of the most important physico-chemical properties of fullerenes. Photoexcited C₆₀ and C₇₀ can cause the electron transfer (type I)¹ or energy transfer (type II)^2,3 reaction under visible light irradiation in quite high quantum yields (quantitative). These reactions have been used to develop new functional materials for the application of photovoltaic devices and photodynamic therapy agents. Especially in the latter application, generation of reactive oxygen species (ROSs)⁴ such as ¹O₂ and O₂•^–5,6is used to affect the biological molecules.

The generation of ¹O₂ has been also used in the organic reaction. Using fullerenes as photocatalyst, oxidation of olefins,⁷ phenols⁸ and sulfides⁹ were reported. In this study, we used C₇₀ for the oxidation of benzylamines. Compared to C₆₀ and other commonly used photosensitizers such as tetraphenylporphyrin (TPP),^10,11 C₇₀ could catalyze the oxidation of benzylamines to corresponding imines efficiently with lower catalyst loading (0.01 mol %). The reaction worked also under the lower energy of lights using blue (max 470 nm) and green (max 520 nm) diodes. Reaction processed in clean manner without any significant amount of side product, and removal of the C₇₀catalyst was carried out easily by just simple precipitation and filtration.

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