BROMINE AUXILIARIES IN PHOTOSYNTHESES OF [5]HELICENES

[摘要] Bromine substituents on benzene rings direct photocyclizations away from their ortho positions. This principle prevents [5]helicenes from photocyclizing and methoxyls from photoeliminating. It makes possible the photosynthesis of [5]helicene and of a tetramethoxy-derivative of [5]helicene.

[发布日期] 1991-11-18