Fluorenes and methylene-bridged polyarenes were easily and efficiently synthesized from haloarenes (or aryl triflates) and diarylethynes by a one-pot, two-step procedure. This protocol involves the palladium-catalyzed cycloisomerization and a subsequent base-mediated retro-aldol condensation. A major advantage is that the starting materials need not have ortho functional groups to complete the annulation. The backbone of the designed products was enlarged using dihaloarenes, highly π-conjugated haloarenes, or diarylalkynes. The mechanism of the formation of benzo[a]fluorene was investigated. The bowl-shaped structure of methylene-bridged indenocorannulene was verified by X-ray crystallography. The photophysical and electrochemical properties of the products thus prepared were investigated.
All Science Journal Classification (ASJC) codes
- Organic Chemistry