Equivalence between parities of two-substituents swaps and mirror reflections in the determination of tetrahedral atom’s chirality: A demonstration with mirrors!

Abstract

The even number of two-substituents swaps for determining the chirality of a tetrahedral stereogenic center is a direct and very simple method but it requires of a practical or theoretical support. In this paper, an odd and even number of swaps are presented as a product of reflections over one or two mirrors which invert and restore, respectively, its absolute configuration. This fact can be illustrated by using two mirrors arranged in a variable angle (180° ≤ α ≤ 0°) in which is possible to appreciate homomorphic and enantiomorphic images depending on the reflection’s parity.