why does cyclohexane prefer the chair conformation?
It eliminates angle and torsional strain
What is ring flipping in cyclohexane?
Conversion of one chair form into the other
What happens to axial/equatorial bonds during ring flip?
Axial become equatorial and vice versa
Why do bulky groups prefer equatorial positions?
They minimise steric repulsion
What are axial bonds?
Bonds perpendicular to the ring plane
What are equatorial bonds?
Bonds roughly in the plane of the ring perimeter
What are configurational isomers?
Isomers that cannot interconvert without breaking bonds
What are optical isomers?
Chiral molecules that rotate plane-polarised light
What structural feature causes chirality?
An sp3 carbon with four different groups
What is a chiral centre?
A carbon with four different substituents
What is an enantiomer?
A non-superimposable mirror image molecule
Do enantiomers have identical physical properties?
Yes except for optical rotation and interactions with chiral environments
What is a racemic mixture?
A 50:50 mixture of enantiomers with no optical activity
