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ORGANIC CHEMISTRY
Dr Nam T. S. Phan
Faculty of Chemical Engineering
HCMC University of Technology
Office: room 211, B2 Building
Phone: 38647256 ext. 5681
Email: ptsnam@hcmut.edu.vn

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Chapter 3: INTRODUCTION TO
REACTION MECHANISMS
Elimination
Electrophilic substitution
Nucleophilic substitution Nucleophilic addition
Electrophilic addition
Reaction mechanism: the description of the
step-by-step process by which reactants
are changed / converted into products

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NUCLEOPHILIC SUBSTITUTION
REACTIONS (SN
)
• A nucleophile: an electron-rich species that can
form a covalent bond by donating 2 electrons to a
positive center
• A nucleophile is any negative / neutral molecule
that has 1 unshared electron pair
• Substitution reaction: chemical reaction in which
1 atom / group replaces another atom / group in the
structure of a molecule
• In a nucleophilic substitution reaction, a
nucleophile attacks / bonds with the positive center

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BIMOLECULAR NUCLEOPHILIC
SUBSTITUTION REACTION (SN
2)

