Premium
Taming Radical Intermediates for the Construction of Enantioenriched Trifluoromethylated Quaternary Carbon Centers
Author(s) -
Calvo Roxan,
ComasVives Aleix,
Togni Antonio,
Katayev Dmitry
Publication year - 2019
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201812793
Subject(s) - hypervalent molecule , chemistry , reagent , trifluoromethyl , trifluoromethylation , lewis acids and bases , enantioselective synthesis , quaternary carbon , catalysis , combinatorial chemistry , fluorine , iodine , organic chemistry , alkyl
Demonstrated herein is the construction of trifluoromethylated quaternary carbon centers by an asymmetric radical transformation. Enantioenriched trifluoromethylated oxindoles were accessed using a hypervalent iodine‐based trifluoromethyl transfer reagent in combination with a magnesium Lewis acid catalyst and PyBOX‐type ligands to achieve up to 99 % ee and excellent chemical yields. Mechanistic studies were performed by experimental and computational methods and suggest a single‐electron transfer induced S N 2‐type mechanism. This example is thereby the first report on the construction of enantioenriched trifluoromethylated carbon centers using hypervalent iodine‐based reagents proceeding through such a reaction pathway.