Chapter 8, Problem 40P

Interpretation Introduction

Interpretation:

The $R-S$ configuration of products obtained in problem 8.39 is to be assigned.

Concept Introduction:

$R-S$ Configuration is used to differentiate between enantiomers.

First, give priority according to Cahn-Ingold-Prelog convention rules:

The higher the atomic mass, the higher will be the priority.

If priority cannot be assigned according to atomic mass, then assign the priority according to the first point of difference.

After giving priority to four groups, rotate the molecule such that the fourth priority group is at horizontal position.

Now, move from 1-2-3; if it is clockwise, then it is $\left(R\right)$ configuration and if it is anti-clockwise, then it is $\left(S\right)$ configuration.

Enantiomers have opposite $R-S$ configuration, that is, if one of the enantiomers is $\left(R\right)$, the other one will have $\left(S\right)$ configuration.