cis-1,2-dimethylcyclopropane

Cis- and trans-1,2-dimethylcyclopropane are stereoisomers, meaning they have the same chemical formula but differ in the spatial arrangement of their atoms. In the cis isomer, the two methyl groups are on the same side of the cyclopropane ring, while in the trans isomer, they are on opposite sides. Unlike conformational isomers, these cis and trans isomers cannot be interconverted by rotation around bonds because the three-membered cyclopropane ring is rigid. This difference in spatial arrangement gives them distinct physical properties, such as different boiling points.123