Photoamination of Alkenylnaphthalenes with Ammonia via Electron Transfer

Article abstract of DOI:10.1246/bcsj.71.1655

The photoamination of l-(2-methyl-l-propenyl)naphthalene (1a) with ammonia in the presence of p-dicyanobenzene (p-DCB) occurred selectively at the alkenyl group but not at the naphthyl group to give l-(2-amino-2-methylpropyl)naphthalene (2a). Similarly, the photoamination of several kinds of alkenylnaphthalenes (1) proceeded selectively at the alkenyl group. The photoamination proceeded via the nucleophilic addition of ammonia to the cation radical of 1 generated by the photoinduced electron transfer to p-DCB to give the aminated radical after deprotonation. Distribution of the positive charge in 1⁺· and the stabilities of the aminated radicals were calculated by the PM3-UHF method. The stabilities of the aminated radicals agreed with the regioselectivity.