Intramolecular photoaddition reactions of (aminoalkyl)styrylamides

Abstract

The photochemical reactions of a family of styrene—spacer—amine molecules in which the spacer consists of a rigid amide group in the middle of a flexible alkane chain have been investigated. Our study of the photophysics of these molecules has shown that the amide linker can facilitate intramolecular styrene—amine exciplex formation (J. Phys. Chem., in press). We report here the photochemical behavior of these amide-linked (aminoalkyl) styrylamides. Several tertiary amines are found to undergo regioselective α-C-H addition to the styrene double bond resulting in the formation of medium-ring lactams. A secondary amine undergoes N-H addition yielding an azalactam. The dependence of these reactions upon spacer structure, amine and amide substitution, and solvent polarity is discussed.