# Are cis and trans isomers examples of diastereomers?

Dec 24, 2014

Yes, cis and trans isomers are examples of diastereomers.

We usually think of diastereomers as optical isomers that are not mirror images of each other.

But a diastereomer is any stereoisomer that is not an enantiomer.

The cis and trans isomers of but-2-ene are isomers that are not mirror images of each other, so they are diastereomers.