Journal of Photosciences

Photoaddition Reactions of N-Methylthiophthalimide with a-Silyl-nelectron Donors via Single Electron Transfer-Desilylation and Hydrogen Atom Abstraction Pathways

Volume 9(2002), 17-22 page

ÀúÀÚ: Ung Chan Yoon, Sun Wha Oh, Seong Chul Moon and Tae Gyung Hyung

   9-1-17.pdf (123.3K)

Keywords: photoaddition reaction  N-methylthiophthalimide  a-silyl-n-electron donors  single electron transfer  hydrogen atom abstraction


Studies have been conducted to explore photoaddition reactions of N-methylthiophthalimide with a-silyl-nelectron donors Et2NCH2SiMe3 , n-PrSCH2SiMe3 and EtOCH2SiMe3.
Photoaddition of a-silyl amine Et2NCH2SiMe3 to N-methylthiophthalimide occurs in CH3CN and benzene to produce non-silicon containing adduct in which thiophthalimide thione carbon is bonded to a-carbon of a-silyl amine in place of the trimethylsilyl group.
In contrast, photoaddition of EtOCH2SiMe3 to N-methylthiophthalimide generates two diastereomeric adducts in which thiophthalimide thione carbon is connected to a-carbon of a-silyl ether in place of a-hydrogen.
Based on a consideration of the oxidation potentials of a-silyl-n-electron donors and the nature of photoadducts, mechanism for these photoadditions involving single electron transfer (SET) -desilylation and H atom abstraction pathways are proposed.