Chirality

Introduction to Chirality and Molecular Structure

Overview of the chemistry module focusing on chirality and its importance in organic chemistry.
Recommended reading from the textbook: Organic Chemistry with Biological Applications (Chapter 5).

Define critical terms related to chirality and stereochemistry:
- Chirality: property of a molecule being non-superimposable on its mirror image.
- Chiral Molecule: a molecule that is chiral.
- Achiral Molecule: a molecule that can be superimposed on its mirror image.
- Stereogenic Center (Chiral Center): the atom in a molecule, usually carbon, that has four different substituents and is chiral.
- Enantiomers: pair of chiral molecules that are non-superimposable mirror images of each other.
Discuss the concept of optical activity, which refers to the ability of chiral compounds to rotate plane-polarized light.
Importance of polarimeters in measuring optical activity.
Define dextrorotatory and levorotatory: directions in which light is rotated and their associated symbols (+/-).
Understanding racemic mixtures, which contain equal amounts of two enantiomers leading to no net optical activity.

Biological molecules are inherently chiral, impacting enzyme-substrate interactions.
Implications of chirality in drug design and efficacy.
Example of amino acids being chiral and their contribution to protein structure.

Two main types of isomerism:
- Constitutional Isomers: same molecular formula but different connectivity.
- Stereoisomers: same molecular formula and connectivity but differ in spatial arrangement.
  - Example: Cis-Trans Isomerism: restricted rotation around a double bond leading to different spatial arrangements.
  - Diastereomers: stereoisomers that are not mirror images.

A chiral molecule cannot be superimposed on its mirror image. Examples include hands and certain sculptural forms.
Achiral molecules: can be superimposed on their mirror images, often due to symmetry.
The term “chirality” derives from the Greek word for