title: Substituent effects in the preparation of naphthacenes by the coupling reaction of diyne-derived zirconacyclopentadienes with tetraiodobenzene.
abstract: The synthesis of a series of substituted naphthacene derivatives through the coupling reaction of zirconacyclopentadienes with diiodobenzenes is reported. A reaction of bis(propargyl)benzenes with zirconacene dibutyl afforded the corresponding tricyclic zirconacyclopentadienes, which reacted with o-diiodobenzenes to afford the corresponding dihydronaphthacenes. The yields of the coupling reactions were dependent on the substituents on both of the zirconacycles and o-diiodobenzenes. The reactions of diphenyl-substituted zirconacycles gave higher yields than those of the alpha,alpha'-dialkyl-substituted derivatives. The iodide functions thus introduced allowed further introduction of substituents by well-established cross-coupling reactions after construction of the naphthacene skeletons.
authors.affiliation: Catalysis Research Center and Graduate School of Life Science, Hokkaido University, and SORST, Japan Science and Technology Agency, Kita-ku, Sapporo 001-0021, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Seri
authors.forename: Hongmei
authors.initials: H
authors.lastname: Qu
authors.forename: Lishan
authors.initials: L
authors.lastname: Zhou
authors.forename: Ken-ichiro
authors.initials: K
authors.lastname: Kanno
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D000478:Alkylation; D003517:Cyclopentanes / Q000737:chemistry*; D053280:Diynes / Q000737:chemistry*; D007462:Iodobenzenes / Q000737:chemistry*; D015394:Molecular Structure; D009279:Naphthacenes / Q000138:chemical synthesis* / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry*
chemical_list: D003517:Cyclopentanes; D053280:Diynes; D007462:Iodobenzenes; D009279:Naphthacenes; C031905:iodobenzene; D015040:Zirconium; C487736:naphthacene