This document presents information on reactive intermediates. It discusses four main types of reactive intermediates: carbocations, carbanions, free radicals, and carbenes. For each type, it describes examples, structures, factors that influence their stability, and common methods of generation. The document contains 19 slides covering an introduction, the four types of intermediates, conclusions, references, and acknowledgments.

1. REACTIVE
INTERMEDIATES
Guided By:
Dr. Sowmya P T
Yuvaraja's college
Presented By:
Inchara R
3rd Semester
Molecular Biology
25/09/2018
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2. CONTENTS
 Introduction
 Types of Intermediates
• Carbocations
• Carboanions
• Free Radicals
• Carbenes
 Conclusion
 References
 Acknowledgement
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3. 3

4. TYPES OF INTERMEDIATES
1. Carbocations:- A positively charged
species.
• E.g.: Methyl cation
• Structure:
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5. • Stability:
a. Simple alkyl Carbocations:
b. Resonance:
Benzyl cation
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Four Canonical structures

6. c. If electron releasing group such as alkyl
group is present adjacent to carbon atom
carrying positive charge will increase the
stability of carbocation.
• Generation:
a. From alkyl halides.
b. From diazonium ions.
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7. 2. Carbanions: A negatively charged
species.
• E.g.: Methyl anion
• Structure:
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8. • Stability:
a. Simple alkyl carbanions:
b. Resonance:
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9. • Generation:
a. From alkyl halides
b. From unsaturated compounds
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10. 3. Free radicals: Species that contain one
or more unpaired electrons.
• E.g.:
• Structure:
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Planar Pyramidal

11. • Stability:
a. Hyperconjugation
b. Resonance
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>

12. • Generation:
a. From photolysis
b. From thermolysis
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+ 2CO2
Di-t-Butyl peroxide
.

13. 4. Carbenes:- Highly reactive species
having a life time less than one second.
• E.g.: Methylene , Dichlorocarbene
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14. • Existence of carbene is of 2 form:
• Stability:
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15. • Generation:
a. From ketenes.
b. From alkyl halides.
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17. REFERENCES
• V.K. Ahluwalia & Rakesh Kumar Parashar.
2007. Organic reaction mechanism Third
edition, Narosa publishing house Pvt. Ltd.,
New Delhi, 669pp.
• Robert thornton Morrison & Robert Neilson
Boyd. 2008. Organic Chemistry sixth edition
Dorling Kindersley Pvt. Ltd., India, 1349pp.
• https://en.m.wikimedia.commons
• https://chem.libretexts.org
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18. ACKNOWLEDGEMENT
I would like to thank the dept. of Molecular Biology
for providing me this opportunity to present the
seminar.
I would also like to thank my guide Dr.P.T. Sowmya
ma’am for her valuable guidance.
Thank you one and all.
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19. THANK YOU
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