Chemistry - STEREO ISOMERISM Question with Solution | TestHub
Which of the following representations will exhibit cis-trans isomerism?
Options:(select one or more)
Answer:
Solution:
Condition: Cis-trans isomerism requires restricted rotation (like double bonds or rings) where both carbons of the system are attached to two entirely different groups.
Options (A) & (B): Both possess acyclic double bonds where each alkenic carbon is bonded to two different substituents, allowing distinct cis and trans geometries.
Option (D): This disubstituted cyclopentane ring exhibits cis-trans isomerism depending on whether the two methyl groups lie on the same side or opposite sides of the ring plane.
Option (C): Inside small rings (less than 8 carbons), cyclic double bonds can only exist in the stable cis form because the trans form suffers from extreme ring strain.
Therefore, representations A, B, and D exhibit cis-trans isomerism.
