Triplet-mediated electron transfer oxygenation of stilbene derivatives with 2,4,6-triphenylpyrylium tetrafluoroborate

✍ Scribed by Ryoichi Akaba; Kenji Ohshima; Yukinori Kawai; Yukiko Obuchi; Akio Negishi; Hirochika Sakuragi; Katsumi Tokumaru

• Book ID: 104212821
• Publisher: Elsevier Science
• Year: 1991
• Tongue: French
• Weight: 287 KB
• Volume: 32
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)71231-7

✦ Synopsis

The triplet state of 2,4.6-triphenylpyrylium tetrafluoroborate (TPP+) has efficiently induced an electron transfer oxygenation of stllbene derivatives.

Although photosensitized electron transfer oxygenation has extensively been studied,2 few studies have been reported on the triplet-mediated electron transfer oxygenation of organic compounds.~ Recently, we have shown that 2,4,6+iphenylpyrylium tetralluoroborate (TPP+) is a suitable sensitizer for the photooxygenation not involving superoxide anion, and suggested that electron transfer occurs in its triplet (?PP+*) as well as in its excited singlet state (lI'PP+*).'t We now wish to report that TPP+ sensitizes efficiently the electron transfer oxygenation of aromatic olefins such as stilbene derivatives mainly through the triplet radical pairs.