Photo-induced Molecular Transformations, Part 123. One-Step Synthesis of 1H-Benzindole-4,9-diones by a New Regioselective Photoaddition of 2-Amino-1,4-naphthoquinone with Various Alkenes and Its Application to the One-Step Synthesis of Kinamycin Skeleton

Article abstract of DOI:10.1002/hlca.19910740518

2,3-Dihydro-1H-benzindole-4,9-diones are formed in one-step in 45-82percent yields by an unprecedented <2+3>-type regioselective photoaddition of 2-amino-1,4-naphthoquinone with various electron-rich alkenes and the <2+3> adducts derived from aminonaphthoquinone with vinyl ethers and vinyl acetate to give 1H-benzindole-4,9-diones including a benzindole-dione with a kinamycin skeleton in 33-72percent yields.A probable pathway leading to the formation of the dihydroindole-dione involving air oxidation of an intermediary hydroquinone is proposed.