Properties of Various Groups as Relevant to the MCAT
Group | Elimination | Addition reactions | Substitution reactions | Acidity/ Basicity | Solubilty in water* |
C-H | Free radical; | Generally neutral | Poor | ||
Carbon-carbon double bond C=C | Electrophilic | Generally | Poor | ||
Hydroxyl -OH | Dehydration | Nucleophilic | Very weak acid | Good | |
Carbonyl C=O | Nucleophilic (e.g. aldol condensation) | Very weak acid a -H acidic ® carbanion | Good | ||
Carboxylic acid -COOH | Nucleophilic (can form esters, acid chlorides, anhydrides, amides, keto acids) | Weak acid | Good | ||
-Halide | Nucleophilic | Generally neutral | Poor | ||
Benzene | Electrophilic aromatic | Generally neutral | Poor | ||
Ether C-O-C | The acid cleavage of ethers involves a nucleophilic substitution | Very weak base | Good | ||
Phenol | -H attached to benzene ring: Electrophilic aromatic | Weak acid | Good | ||
Amine - NH2 | Amine acts as a nucleophile in SN2 reaction with acid chloride to form an amide; similar reaction with alkyl halides to form alkylamines | Weak base | Good |
* Generally, a compound is water-soluble if it has only one to three carbon atoms and a hydrophilic group, especially one that can form hydrogen bonds with water molecules.