E

Enantiomers Explained!

      Enantiomers are usually explained as "mirror images of each other." This is a really good explanation for most people, but personally, it doesn't really give me an image to work with in my head. I had trouble understanding how the molecule was different from its reflection. To the left you can see how the two molecules are enantiomers because they are reflected. And while that's all well and good, and makes it easy to come up with an enantiomer by drawing a line and copying the reflection over, the concept doesn't click for me through this. 

     Another way to look at it, is to imagine that all of the 3D bonds are flipped once. The two molecules to the right are the same set of enantiomers as the above! Make sense? Just by switching two of the bonds' locations, you form the enantiomer. 

    

      So then, what's a diastereomer? Diasteromers are stereoisomers that are different but not enantiomers. Look at the image below. Just because it's big doesn't mean it's complicated, the concept is what's important. Look at the enantiomers below. Again, all of the 3D bonds are flipped once to make it an enantiomer. Diastereomers are different. Only some of the 3D bonds are flipped. This means that they won't be mirror images, and thus can't be enantiomers. So, that leaves the last category: Diastereomers.