Chapter 25.2, Problem 3P

Interpretation Introduction

Interpretation:

Among the four Fischer projections of glyceraldehydes which represent the same enantiomer is to be stated.

Concept introduction:

In Fischer projection formula, a tetrahedral carbon is represented by two crossed lines. The horizontal line represents bonds coming out of the page and vertical lines represent bonds moving in to the page.

For assigning R or S configuration, the four groups attached to the chiral center are arranged in the order of priority by applying sequence rules. The molecule is then oriented in such a way that the group of lowest priority points away from the viewer. If the arrangement of highest priority to second highest priority to third highest priority is clockwise then R configuration is assigned. If the arrangement of highest priority to second highest priority to third highest priority is counterclockwise then S configuration is assigned.

To state:

Among the four Fischer projections of glyceraldehydes which represent the same enantiomer.