Click on the below links to download notes of each unit:

Unit 1: Basic Concepts & Substitution




Unit 2: Addition & Elimination

Unit 3: Reaction Intermediates & Molecular Rearrangement

Unit 4: Photochemistry & Synthetic Methods

Please note that these are the units that come under the Mechanism of Organic Reactions. You don't have to study all the chapters. Only study chapters that are in your syllabus.

For your syllabus, you can visit your university!

Disclaimer: The study material provided on this website is taken from the eGyankosh official website. Here's how you can download free study material from IGNOU: How to Download IGNOU Study 
Material?