Optical isomerism in organic chemistry .

Explore the fascinating world of optical isomerism, a fundamental concept in chemistry. This presentation covers the basics of optical isomerism, including:

- Definition and explanation of optical isomerism
- Types of optical isomers: enantiomers, dextrorotatory, and levorotatory
- Meso compounds and racemic mixtures
- Chirality and stereocenters
- Examples of optical isomerism in real-life molecules
- Importance of optical isomerism in chemistry and pharmacology

Learn about the science behind mirror images and how it impacts our understanding of molecular structure and properties. This presentation is perfect for students, educators, and professionals in the field of chemistry.

1. An optically active compound can exist in two isomeric forms which rotate the plane of polarized light in opposite directions. These are called Optical Isomers and the phenomenon is known as Optical Isomerism .

2. Dextrorotatory Isomer The isomer which rotates the plane of polarized light to the right (clockwise direction) is known as Dextrorotatory Isomer or (+) isomer . Levorotatory Isomer The isomer which rotates the plane of polarized light to the left (anticlockwise direction) is known as the Levorotatory Isomer or (-) isomer. These isomers are called enantiomers. Enantiomers

3. Stereoisomers which are not mirror images of each other are called diastereomers.

4. Optical Isomerism of Lactic Acid Lactic acid (2-Hydroxypropanoic acid) is an example of a compound which shows optical isomerism. It contains one asymmetric carbon atom. Two three-dimensional structures are possible for Lactic acid and called enantiomers.

5. Thus, three form These structures are not identical because they cannot be superimposed on each other. Such non superimposable mirror image forms are optical isomers of lactic acid are known. Two (+ and - form) are optically active and third one, equimolar mixture of (+) and (-) form is optically inactive called racemic mixture, as it does not rotate the plane of polarized light.

6. Racemic Mixtures: Definition: An equimolar mixture of two enantiomers, which is optically inactive .

7. Optical Isomerism of Tartaric Acid Tartaric acid (2,3-Dihydroxybutanedioic acid) contains two asymmetric carbon atoms. Four isomeric forms of tartaric acid are known. Asymmetric carbons

8. (+) Tartaric Acid It rotates the plane of polarized light to the right (clockwise direction) and is called dextrorotatory . (-) Tartaric Acid It rotates the plane of polarized light to the left (anticlockwise direction) and is called levorotatory

9. Meso-Tartaric Acid : It posses a plane of symmetry and is optically inactive. This optically inactive form is internally compensated. (±) Tartaric Acid: It does not rotate the plane of polarized light. That is, it is optically inactive. It is an equimolar mixture of (+) and (-) forms (racemic mixture ).