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Published on: April 4, 2014
Thiobenzoic Acid-Catalyzed Cα-H Cross Coupling of Benzyl Alcohols with α-Ketoacid Derivatives
Kaichi Sato1, Hiromichi Egami1, Yoshitaka Hamashima1
1School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
Abstract:
The C-H alkylation of benzyl alcohols with α-ketoacid derivatives was achieved in the presence of thiobenzoic acid with or without Ru or Ir photoredox catalysts. The thiobenzoic acid serves as a photoexcited single-electron reducing reagent and a hydrogen atom transfer catalyst, while addition of the metal photoredox catalyst assists the electron transfer and improves the reaction efficiency. Various functional groups were tolerant of the reaction conditions, and sterically hindered diols were produced in good to high yield.
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