title: Coupling reaction of zirconacyclopentadienes with dihalonaphthalenes and dihalopyridines: a new procedure for the preparation of substituted anthracenes, quinolines, and isoquinolines.
abstract: Reactions of tetraiodobenzene with zirconacyclopentadienes, which were conveniently prepared from two alkynes (or diynes) and zirconocene complexes, afforded 1,2,3,4-tetrasubstituted diiodonaphthalene derivatives in good isolated yields. These 1,2,3,4-tetrasubstituted diiodonaphthalene derivatives could be converted to 1,2,3,4,5,6,7,8-octasubstituted anthracene derivatives by reaction with a second zirconacyclopentadiene. When the two zirconacyclopentadienes were different, unsymmetrical anthracenes such as 1,2,3,4-tetraethyl-5,6,7,8-tetraphenylanthracene (68% isolated yield) were obtained. On the other hand, treatment of a 2,3-dihalopyridine such as 2-bromo-3-iodopyridine with zirconacyclopentadienes gave 5,6,7,8-tetrasubstituted quinoline derivatives in good to high yields. 3,4-dihalopyridines such as 4-chloro-3-iodopyridine reacted with zirconacyclopentadienes to afford 5,6,7,8-tetrasubstituted isoquinoline derivatives in good to high yields.
authors.affiliation: Catalysis Research Center and Graduate School of Pharmaceutical Sciences, Hokkaido University, Japan.
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Takahashi
authors.forename: Yanzhong
authors.initials: Y
authors.lastname: Li
authors.forename: Petr
authors.initials: P
authors.lastname: Stepnicka
authors.forename: Masanori
authors.initials: M
authors.lastname: Kitamura
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Liu
authors.forename: Kiyohiko
authors.initials: K
authors.lastname: Nakajima
authors.forename: Martin
authors.initials: M
authors.lastname: Kotora