McMurry (Kap.4,5)

Question 1

Are cyclohexane common in nature?

Answer 1

It is the most common one cycloalkane and occurs widely in nature.

Question 2

What is the conformer that cyclohexane adapts?

Answer 2

It is called the chair conformer.

Molecules, particularly cyclohexane, adopt the chair conformer because it minimizes strain, making it the most stable conformation.

• Angle strain
• Torsional strain
• Steric strain

Question 3

How is the strain of the cyclohexane?

Answer 3

It is strain free (neither angle nor torsional strain).

All the bond angles are nearly 109 grader. All the C-H bonds are staggered.

Question 4

How to draw a chair conformer?

Answer 4

See page 98 on the tutorial

Question 5

What is the twist boat conformer?

Answer 5

Another conformer that is also a nearly strain free one.

However it does have both steric and torsional strain. A little bit higher in energy then the chair conformer.

Question 6

When does molecules adopt the twist chair conformer?

Answer 6

Molecules adopt the twist hair conformer under special circumstances.