Nucleophilic substitution

Nucleophilic substitution

1. nucleophile

   • are reagents that attack and form bonds with electron deficient carbons
   • usually a negatively charged ion
   • or a partially negative atom
   • has a lone pair of electrons
     • used to make a covalent bond
   • common nucleophiles
     • :OH-
     • :NH3
     • :CN-

2. rules

   • curly arrow
   • goes from electrons to +
   • goes from bond to atom
   • rate of reaction
     • increases as you go down the group
       • as bond strength decreases

3. for the hydroxide ion, :OH-

   • take place at room temperature
   • called a hydrolysis reaction
   • add ethanol
   • an alcohol is formed

4. with cyanide ions, :CN-

   • you get a nitrile
   • has one extra carbon

5. with ammonia, :NH3

   • used with excess conc solution of ammonia in ethanol
   • carried out under pressure
   • produces a primary amine, RNH2
   • H's have +
   • N has a -
   • add 2 NH3's
   • end up with NH4X
   • one of the H's becomes +

6. uses of nucleophilic substitution

   • primary amine
     • secondary amine
       • tertiary amine
   • alcohol
     • aldehyde
       • carboxylic acid
   • nitriile
     • primary amine
     • carboxylic acid