I just completed a lab called "Acid-Catalyzed Dehydration of an Alcohol: Synthesis of 2-Octenes."

I started with 2-octanol and the lab instructions said the product had the possibility of being 1-octene, trans-2-octene, and/or cis-2-octene. I did end up with trans-2-octene (based on the IR spectrum). BUT, I'm not sure about how to answer this question:

Why should trans-2-octene be the major product?

Thank you.

1 answer

It is the most stable product that can be formed Because it is an E1 reaction, it follows Zaitzev's rule and will form the most highly substituted alkene. And Trans is always the most stable of the two choices, cis or trans.