1,4-Dichlorobut-2-ene are organochlorine compounds with the formula . Cis and trans isomers exist. These compounds are intermediates in the industrial production of chloroprene. They are main impurity in technical grade chloroprene.
1,4-Dichlorobut-2-ene (both isomers) are produced by chlorination of butadiene:
It is isomerized to 3,4-dichlorobut-1-ene by heating to temperatures of 60âÂÂ120 ðC in the presence of a catalyst:
The resulting 3,4-dichlorobut-1-ene is a precursor to chloroprene, the monomer for the synthetic rubber neoprene.
1,4-Dichlorobut-2-ene is a precursor to various heterocycles. The (E)-isomer is also one of the starting materials for the poriferic natural product sceptrin.