Why is cis–trans isomerism common in alkenes?
1 Answer
Jun 11, 2015
Cis-trans isomerism is common in alkenes because there is restricted rotation about double bonds.
Explanation:
For example, an alkene such as but-2-ene has two different groups on each alkene carbon.
It can exist as
The double bond prevents rotation about the C=C axis.
So the molecule exists as two isomers, with substituents on the same side (cis) or on the opposite side (trans) of the double bond.