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Updated: Oct 13, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Convenient synthesis of alpha-trifluoromethylated acyloins from alpha-hydroxy or alpha-amino acids
M Kawase1, S Saito, T Kurihara
1Faculty of Pharmaceutical Sciences, Josai University, Sakado, Saitama, Japan. kawasema@josai.ac.jp
Abstract:
Alpha-trifluoromethylated acyloins (2 and 6) have been prepared from alpha-hydroxy acids (1), N-acylprolines (5) or N-acyl-N-alkyl alpha-amino acids (8) by novel transformation reactions with trifluoroacetic anhydride (TFAA) in the presence of pyridine. The former reaction of 1 could proceed through mesoionic 1,3-dioxolium-4-olates, whereas the latter two reactions of alpha-amino acids (5 and 8) could involve mesoionic 1,3-oxazolium-5-olates. The reaction of 1 with TFAA shows more potential for practical applications because of the ready availability of the starting materials and ease of manipulation.
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