Stéréochiralité

Stéréochiralité, often simply referred to as chirality, is a fundamental property in chemistry and physics. It describes an object or molecule that is non-superimposable on its mirror image. Think of your left and right hands; they are mirror images of each other, but you cannot perfectly overlay one onto the other. This property is known as chirality. In chemistry, chiral molecules exist as a pair of enantiomers, which are stereoisomers that are non-superimposable mirror images.

The presence of a stereocenter, typically a carbon atom bonded to four different groups, is a common source of chirality in organic molecules. However, chirality can arise from other structural features as well. The specific three-dimensional arrangement of atoms in a chiral molecule is crucial. Enantiomers have identical physical properties like melting point, boiling point, and density, but they can differ significantly in their interactions with other chiral entities.

This difference is particularly important in biological systems, as enzymes and receptors are themselves chiral. Consequently, enantiomers of a drug can exhibit vastly different pharmacological effects, with one enantiomer being therapeutic and the other inactive or even toxic. The study and control of stereochirality are therefore essential in fields such as pharmaceuticals, materials science, and molecular biology. The synthesis of specific enantiomers, known as asymmetric synthesis, is a highly developed area of organic chemistry.