Substituted cyclohexanes - 4 | Cycloalkanes

Organic Chemistry 1 - Substituted cyclohexanes - 4

Draw the chair conformations of the following 2D-representation cyclohexanes:

 

Which stereoisomer (trans or cis) of 1,2-dimethylcyclohexane is the most stable? 

What about 1,3-dimethylcyclohexane?

 

The trans-1,2-dimethylcyclohexane is the most stable stereoisomer of 1,2-dimethylcyclohexane

The cis-1,3-dimethylcyclohexane is the most stable stereoisomer of 1,3-dimethylcyclohexane