title: Tetrabromobutatriene: completing the perhalocumulene series.
abstract: [structure: see text] Tetrabromobutatriene, C(4)Br(4), can be prepared directly from dibromobutadiyne by reaction with Br(2) at -25 degrees C in concentrated hexanes solution. The cumulene precipitates out of the reaction mixture as a yellow powder. Under palladium-catalyzed coupling conditions, C(4)Br(4) can undergo allylic rearrangement, giving a mixture of products, including some with butenyne backbones. However, in furan solution, C(4)Br(4) reacts cleanly at its central double bond to give the furan Diels-Alder adduct. Under Suzuki conditions, this adduct reacts at the furan double bond rather than at bromide.
authors.affiliation: Department of Chemistry, State University of New York, Stony Brook, New York 11794-3400, USA.
authors.forename: Pei-Hua
authors.initials: PH
authors.lastname: Liu
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Webb
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Nancy S
authors.initials: NS
authors.lastname: Goroff