@misc{oai:repo.qst.go.jp:00071064,
 author = {Kawashima, Tomonori and Nakanishi, Ikuo and Ohkubo, Kei and Fukuzumi, Shunichi and Ozawa, Toshihiko and Matsumoto, Kenichiro and 川島 知憲 and 中西 郁夫 and 松本 謙一郎},
 month = {Mar},
 note = {Dismutation of superoxide is a primary scavenging reaction of reactive oxygen species (ROS) using the metalloprotein, superoxide dismutase (SOD). SOD is known to contain redox active metal ions, such as Mn, Cu-Zn, and Fe, in its active center. However, there are few reports about dismutation of free radicals by redox-inactive metal ions. In this study, we report the dismutation of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH radical) as an ROS model catalyzed by redox-inactive metal ions with Lewis acidity. In acetonitrile at ambient temperature, the absorption band at 519 nm due to DPPHradical was decreased by addition of Sc(OSO2CF3)3, which has a very strong Lewis acidity. In the case of Mg(ClO4)2 as a weaker Lewis acid than Sc3+, no consumption of DPPHradical was observed in the presence of Mg2+. On the other hand, upon addition of Mg(ClO4)2 with acetic acid, DPPHradical was quenched efficiently. In summary, a strong Lewis acid, Sc3+, can promote dismutation of DPPHradical, while protons are required for the dismutation of DPPHradical to occur in the presence of a weak Lewis acid, Mg2+., International Free Radical Winter School in Muikamachi},
 title = {Dismutation of 2,2-Diphenyl-1-picrylhydrazyl Radical Catalyzed by Lewis and Bronsted Acids},
 year = {2013}
}