Chapter 7.SE, Problem 50AP

Interpretation Introduction

Interpretation:

The observation that cyclodecene can exist in both cis and trans forms, but cyclohexene cannot.

Concept introduction:

Among cis and trans isomers, the cis isomers are usually less stable due to the steric interferences that exist in these isomers. But the situation becomes quite different in the case of small and medium sized rings having up to seven atoms. In these cases twisting the ring so as to attain the trans configuration will introduce a severe strain in the molecule making them unstable. However in the case rings with eight and more carbon atoms the rings become large enough to twist without any strain leading to the existence of trans forms.

To Explain:

The observation that cyclodecene can exist in both cis and trans forms, but cyclohexene cannot.