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Nucleophilic Substitution reactions

Nucleophilic substitution at sp3 C
Nucleophilic substitution reactions are an important class of reactions that allow the interconversion of functional groups, for example R-OH ® R-Br.

Nucleophilic substitution will be explored in much more detail in chapter 8.

What does the term "nucleophilic substitution" imply ?

A nucleophile is an the electron rich species that will react with an electron poor species.
A substitution implies that one group replaces another

Curly arrows for S<sub>N</sub>2

There are two fundamental events in these substitution reactions:

  1. formation of the new bond to the nucleophile
  2. breaking of the bond to the leaving group
Depending on the relative timing of these events, two different mechanisms are possible:
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organic chemistry © Dr. Ian Hunt, Department of Chemistry University of Calgary