Question

Question: Label each stereogenic center as RorS.

Short answer

Answer

a. The stereogenic center of compound a is S.

b. The stereogenic center of compound b is S.

c. The stereogenic center of compound c is S.

d. The stereogenic center of compound d is S.

Step-by-step solution

Stereogenic center

The carbon atom at the stereogenic center can possess sp² or sp³ hybridization. A stereogenic center can be connected to three or four groups.

Fischer projection formula

The horizontal bonds proceed forward and are indicated as wedges in a Fischer projection formula. The vertical bonds move backward and are indicated as dashed wedges.

Labelling the stereogenic center of each compound

The Fischer projection formula of the molecule is converted to be represented as wedges and dashes. The groups are numbered in the order of their priority. The compound is assigned R if the rotation proceeds clockwise, and the compound is assigned S if the rotation proceeds in the anticlockwise direction.

a. The stereogenic center of compound a is S as the rotation proceeds in the anticlockwise direction. The stereogenic center can be given as:

Stereogenic center of compound a

b. The stereogenic center of compound b is S as the rotation proceeds in the anticlockwise direction. The stereogenic center can be given as:

Stereogenic center of compound b

c. The stereogenic center of compound c is S as the rotation proceeds in the anticlockwise direction. The stereogenic center can be given as:

Stereogenic center of compound c

d. The stereogenic center of compound d is S as the rotation proceeds in the anticlockwise direction. The stereogenic center can be given as:

Stereogenic center of compound d