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Updated: Jun 30, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
(1-Naphthyl)(trifluoromethyl) O-carboxy anhydride as a chiral derivatizing agent: eclipsed conformation enforced by
Olivier Thillaye du Boullay1, Aurélie Alba, Fatima Oukhatar
1Laboratoire Hétérochimie Fondamentale et Appliquée du CNRS (UMR 5069) Université Paul Sabatier, 118, route de Narbonne, 31062 Toulouse Cedex 09, France.
Abstract:
The preparation of the (1-naphthyl)(trifluoromethyl) O-carboxy-anhydride 1 and its use as a chiral derivatizing agent with several alpha-chiral primary amines are reported. The very large Delta delta(RS) values observed in (1)H NMR have been correlated with a marked preference of the corresponding alpha-hydroxy-amides for the eclipsed conformation. In comparison, the related O-methylated amides are shown to adopt staggered conformations, which substantiates the critical role of intramolecular hydrogen bonding in maximizing the anisotropic effect.
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