Cyclohexane A Strain-Free Cycloalkane

The cyclohexane ring is one of the most common and important structural units in organic chemistry. Its substituted derivatives exist in many natural products (see Section 4-7), and an understanding of its conformational mobility is an important aspect of organic chemistry. Table 4-2 reveals that, within experimental error, cyclohexane is unusual in that it is free of bond-angle or eclipsing strain. Why  

Cyclohexane also has several less stable conformations 

Chair cyclohexane (Nearly tetrahedral bond angles no eclipsing hydrogens) 

Being able to draw cyclohexane chair conformations will help you learn the chemistry of six-membered rings. Several rules are useful. 

Rgure 4-8 Twist-boat to twist-boat flipping of cyclohexane proceeds through the boat conformation. 

---