ELECTROLYTIC TRANSFORMATION OF FLUOROORGANIC COMPOUNDS .5. ANODIC CYANATION OF 2,2,2-TRIFLUOROETHYLAMINES

Anodic nucleophilic substitution reaction of amines attracts much interest because of its synthetic utility. Various functional groups can be introduced into the exposition to the nitrogen atom in one step.2 It is interesting that electrochemical reaction shows characteristic regiochemistry different from common homogeneous reaction in many cases. Anodic substitution usually takes place at a less substituted carbon atom preferably. For example, it is known that anodic methoxylation of N-ethyl-N-methylaniline occurs at the methyl group exclusively.3 On the other hand, we have reported that the regioselectivity was dramatically changed in the case of anodic methoxylation of 2,2,2-trifluoroethylamines, i.e., the methoxylation preferably takes place at the a-position to the trifluoromethyl group.4 Although anodic cyanation of amines is expected to provide a promising method for the preparation of a-amino nitriles as versatile synthetic precursors, there are only a few reports on the anodic a-cyanation reaction of amines.5 The regiochemistry of the oxidative a-cyanation of amines is important and interesting from synthetic and mechanistic aspects not only in electrochemistry but also in organic chemistry.6 Our interest is therefore focused on the effects of the trifluoromethyl group both on the oxidation potentials of the amines and on the regiochemistry of the anodic cyanation reaction. We report here a remarkable difference in the regioselectivity between the anodic cyanation and methoxylation reactions of 2,2,2-trifluoroethylamines. © 1990, American Chemical Society. All rights reserved.