Base‐Controlled Chemoselective Reaction of High‐Valent Cu(III)−CF3 Compounds with Anilines: Access to Formamides or Hydrazines.

This study reports reactivity properties of Cu(III)−CF3 compounds with anilines, wherein basicity‐dictated distinct reactivities are achieved, giving rise to formamides or hydrazines. Competing generation of difluorocarbene and N‐centered radical is proposed that is controlled by the basicity of the reaction solution. Specifically, under acidic or neutral conditions, reaction of anilines with Cu(III)−CF3 compounds produces formamides, where difluorocarbene is involved, undergoing aniline formylation. In contrast, in the presence of a base, this same reaction selectively gives hydrazines instead, where Cu(III)−CF3 compounds act as an oxidizing reagent to allow dehydrogenative N−H/N−H coupling of two anilines through an N‐centered radical. The scope of both reactions is studied, and application to medicinally relevant compounds is shown. This study shows the unusual use of high‐valent Cu(III) trifluoromethyl compounds as hydrogen‐abstracting reagents to allow dehydrogenative reactions. [ABSTRACT FROM AUTHOR]