Chemoselective Catalytic α-Oxidation of Carboxylic Acids: Iron/Alkali Metal Cooperative Redox Active Catalysis

• DOI: 10.1021/jacs.0c00727
• Publication Date: 2020-02-13T11:43:07Z
• Authors: Tsukushi Tanaka; Ryo Yazaki; Takashi Ohshima
• Keywords: 01 natural sciences; 0104 chemical sciences

We developed a chemoselective catalytic activation of carboxylic acid for 1e– radical process. α-Oxidation variety acids, which preferentially undergo undesired decarboxylation under conditions, proceeded efficiently the optimized conditions. Chemoselective enolization was also achieved even in presence more acidic carbonyls. Extensive mechanistic studies revealed that cooperative actions iron species and alkali metal ions derived from 4 Å molecular sieves substantially facilitated enolization. For first time, unprotected without external addition stoichiometric amounts Brønsted base. The formed redox-active heterobimetallic enediolate coupled with free TEMPO, providing synthetically useful α-hydroxy keto derivatives.