Intro to 4 Basic Types of Reaction: SN1 SN2 E1 E2 - Updated 2024!

After introducing electrophile and nucleophile, let's talk about SN1, SN2, E1 and E2.

Let's see what they mean first:
SN1: First-Order Nucleophilic Substitution
SN2: Second-Order Nucleophilic Substitution
E1: First-Order Elimination
E2: Second-Order Elimination 

 So basically, these 4 types of reactions are categorized into 
 Nucleophilic Substitution and Elimination. 

  • Nucleophilic Substitution means one thing is substituted by something else, which is a nucleophile (to make it nucleophilic)
  • Elimination always form a double bond product because as something is eliminated, the remained  electrons form a double bond 

The condition for each of these reactions are different (solvent, leaving group, reactant bulkiness, etc) and the ability to classify them is crucial. Here is a table summarized all we need to know about them.  


source: www.pinstopin.com


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