Question 31.15 - Organic Chemistry

Question

Draw the enantiomer and any two diastereomers of cholesterol. Does the OH group of cholesterol occupy an axial or equatorial position?

Step-by-Step Solution

Answer

Answer

Step-by-Step Solution Step 1: Cholesterol

The cholesterol structure has the chemical formula ${\mathbf{C}}_{\mathbf{27}}{\mathbf{H}}_{\mathbf{46}}\mathbf{O}$ , and the OH group is attached at the third position of cholesterol. Some H groups are above the plane, and some are below the plane, but the OH group is seated equatorial.

Step 2: Structure of cholesterol

The structure of cholesterol contains three 6-membered rings and one 5-membered ring. The OH group in cholesterol occupies an equatorial position.

Structure of cholesterol

Step 3: Enantiomer of cholesterol

The enantiomer of cholesterol is shown as the mirror image of cholesterol. All the groups which are below the plane become on the plane. The OH group of cholesterol becomes the dash-wedge and is shown as:

Enantiomer of cholesterol

Step 4: Diastereomers of cholesterol

The diastereomers of cholesterol are shown below. The two diastereomers are non-mirror images. The OH group is different in the first diastereomer, and the H group is below the plane in the second.

Two diastereomers of cholesterol