title: Palladium-Catalyzed Reaction of Haloarenes with Diarylethynes: Synthesis, Structural Analysis, and Properties of Methylene-Bridged Arenes.
abstract: 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.
authors.affiliation: Department of Chemistry, National Cheng Kung University , No. 1 Ta-Hsueh Road, 70101 Tainan, Taiwan.
authors.forename: Che-Wei
authors.initials: CW
authors.lastname: Lee
authors.affiliation: Department of Chemistry, National Cheng Kung University , No. 1 Ta-Hsueh Road, 70101 Tainan, Taiwan.
authors.forename: En-Chih
authors.initials: EC
authors.lastname: Liu
authors.affiliation: Department of Chemistry, National Cheng Kung University , No. 1 Ta-Hsueh Road, 70101 Tainan, Taiwan.
authors.forename: Yao-Ting
authors.initials: YT
authors.lastname: Wu