Heterocycle annulation of enolizable vinyl quinone imides. Dihydroquinolines and quinolines from thermal 6pi-electrocyclizations and indoles from photochemical cyclizations.

[reaction: see text] Enolizable vinyl quinone mono- and diimide substrates yield protected 6-hydroxy and 6-amino dihydroquinolines by thermal electrocyclization. Aromatization provides the corresponding quinolines in quantitative yields. The quinone monoimide substrates undergo clean photochemical conversion to 5-hydroxy indoles.