Photochemical and free-radical processes in benzil-amine systems. Electron-donor properties of α-aminoalkyl radicals

Abstract

The reactions of α-aminoalkyl radicals of the type CH3ĊHN(C2H5)2 with benzil to produce the corresponding ketyl radical (or the radical anion) take place with rate constants in the 1 × 109 M-1 s-1 range and are among the fastest known radical-molecule reactions. The photochemistry of benzil in the presence of triethylamine involves initial hydrogen abstraction followed by carbonyl reduction by the α-aminoalkyl radical. An earlier interpretation of the experimental data based on a relatively long-lived exciplex is incorrect. © 1981 American Chemical Society.