Which of the following molecules can exist as cis-trans isomers?
A) 1,1-dimethylcyclobutane
B) 1,2-dimethylcyclobutane
C) both 1,1-dimethylcyclobutane and 1,2-dimethylcyclobutane
D) none of these

Question

Quizplus · Accepted Answer

Cis-trans isomerism requires that each carbon of the double bond (or in cyclic compounds, the carbons involved in the ring) have two different groups attached to it. 1,2-dimethylcyclobutane meets this criterion, allowing for cis (same side) and trans (opposite side) configurations of the methyl groups relative to the plane of the ring. 1,1-dimethylcyclobutane does not allow for cis-trans isomerism because both methyl groups are attached to the same carbon, making them identical in spatial arrangement.

Which of the Following Molecules Can Exist as Cis-Trans Isomers