Irradiation of 1,3-Dienes in the Presence of Anilines

Article abstract of DOI:10.1021/jo00220a066

Acetonitrile solutions of 1,3-cyclohexadiene or 2,5-dimethyl-2,4-hexadiene and aniline, its N-methylated derivatives, Et2NH, or Et3N were irradiated at 350 nm.Adducts (3-anilinoalkenes) were observed in the presence of the primary or secondary anilines but not with the tertiary aniline or the alkylamines.The products are interpreted as arising via an electron-transfer intermediate within the singlet manifold.The cyclic diene gives competitive <2 + 2> and <4 + 2> dimerization apparently via the triplet.A third diene cyclooctadiene gave no observable chemistry in appreciable amounts.