Ch. 7 - Substitution ReactionsWorksheetSee all chapters
All Chapters
Ch. 1 - A Review of General Chemistry
Ch. 2 - Molecular Representations
Ch. 3 - Acids and Bases
Ch. 4 - Alkanes and Cycloalkanes
Ch. 5 - Chirality
Ch. 6 - Thermodynamics and Kinetics
Ch. 7 - Substitution Reactions
Ch. 8 - Elimination Reactions
Ch. 9 - Alkenes and Alkynes
Ch. 10 - Addition Reactions
Ch. 11 - Radical Reactions
Ch. 12 - Alcohols, Ethers, Epoxides and Thiols
Ch. 13 - Alcohols and Carbonyl Compounds
Ch. 14 - Synthetic Techniques
Ch. 15 - Analytical Techniques: IR, NMR, Mass Spect
Ch. 16 - Conjugated Systems
Ch. 17 - Aromaticity
Ch. 18 - Reactions of Aromatics: EAS and Beyond
Ch. 19 - Aldehydes and Ketones: Nucleophilic Addition
Ch. 20 - Carboxylic Acid Derivatives: NAS
Ch. 21 - Enolate Chemistry: Reactions at the Alpha-Carbon
Ch. 22 - Condensation Chemistry
Ch. 23 - Amines
Ch. 24 - Carbohydrates
Ch. 25 - Phenols
Ch. 26 - Amino Acids, Peptides, and Proteins

We can use reactions we’ve learned in the past (particularly acid-base reactions) to understand substitution. In fact, substitution is just a category of Lewis acid-base reactions! 

Concept #1: Remembering general patterns of reactions.  

Remember: Nucleophiles always attack electrophiles!

Let’s take a stroll through the reactions we’ve already learned so we can make this connection. 

Bronsted-Lowry Reactions:

Concept #2: Nucleophiles and Electrophiles can react in Bronsted-Lowry Reactions.  

In Bronsted-Lowry reactions, a nucleophile attacks an electrophile with an acidic hydrogen, and removes it. 

Lewis Reactions:

Concept #3: Nucleophiles and Electrophiles can react in Lewis Acid-Base Reactions.  

In Lewis reactions, a nucleophile attacks an electrophile without an acidic hydrogen, but with an empty orbital, to yield a covalent bond. 

Substitution Reactions:

Concept #4: Nucleophiles and Electrophiles can react in Substitution Reactions. 

In substitution reactions, a nucleophile attacks an electrophile without an acidic hydrogen, or an empty orbital, so a covalent bond MUST be broken to preserve the octet of the electrophile.

  • The bond that is broken to allow this reaction to take place makes a leaving group

Example #1: Predict the product. Identify all of the chemical species in the following reaction.