Related Experiment Video
Updated: Aug 14, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Tetrabromobutatriene: completing the perhalocumulene series
Pei-Hua Liu1, Lei Li, Jeffrey A Webb
1Department of Chemistry, State University of New York, Stony Brook, New York 11794-3400, USA.
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.
Related Concept Videos
Regioselectivity of Electrophilic Additions-Peroxide Effect
Halogenation of Alkenes
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Formation of Halohydrin from Alkenes
Electrophilic 1,2- and 1,4-Addition of HX to 1,3-Butadiene
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group with both...
Electrophilic 1,2- and 1,4-Addition of X2 to 1,3-Butadiene

