Tetraorganylborate salts as convenient precursors for photogeneration of tertiary amines

Abstract

Photoreactions of p-(benzoyl)benzyl trisubstituted ammonium tetraorganylborate salts for the generation of tertiary amines in solution and rigid matrices are described. Structural modification of the complexes allows study of the influence of steric and electronic effects on the photogeneration of amines. Flash photolysis, cyclic voltammetry and product analysis indicate that single electron transfer from borate to excited benzophenone is followed by homolytic C–N bond cleavage. Photoliberation of the tertiary amine is controlled by the rate of the electron transfer reaction.

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