Chapter 6 Properties and Reactions of Haloalkanes

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Chapter 6 Properties and Reactions of
Haloalkanes

• Lecture 2
• Sections 6.4-6.6
• Kinetics and Stereochemistry of the SN2 Reaction

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Nucleophilic Substitution
What are the kinetics of the reaction? What is
the mechanism of the reaction? What about
molecules with stereocenters?
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Kinetics of Nucleophilic Substitution
Doubling the amount of chloromethane doubles the
reaction rate Doubling the amount of hydroxide
also doubles the reaction rate
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Kinetics of Nucleophilic Substitution
Rate kCH3ClHO- mol L-1 s-1
Bimolecular Nucleophilic Substitution SN2
Reaction
The reaction is CONCERTED Bond-breaking and
bond-making take place at the same time
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Stereochemistry Frontside vs. Backside
Displacement
Frontside Attack
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Stereochemistry Frontside vs. Backside
Displacement
Backside Attack
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Reaction Actually Proceeds by Backside
Displacement
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Orbital Picture of SN2 Reaction
Transition State
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Potential Energy Diagrams
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SN2 Reaction Energy Diagram
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Inversion of Configuration
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Inversion of Configuration