53978-00-0Relevant articles and documents
Tetrabromobutatriene: Completing the perhalocumulene series
Liu, Pei-Hua,Li, Lei,Webb, Jeffrey A.,Zhang, Yi,Goroff, Nancy S.
, p. 2081 - 2083 (2007/10/03)
Tetrabromobutatriene, C4Br4, can be prepared directly from dibromobutadiyne by reaction with Br2 at -25°C in concentrated hexanes solution. The cumulene precipitates out of the reaction mixture as a yellow powder. Under palladium-catalyzed coupling conditions, C4Br4 can undergo allylic rearrangement, giving a mixture of products, including some with butenyne backbones. However, in furan solution, C4Br4 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.
