Questions 7 - 13 refer to the reaction shown below. The most probable mechanism for this reaction is S N 2. 8. Briefly explain your mechanism choice for the previous question. A nucleophilic substitution reaction of this nature will proceed by the S N 2 mechanism in preference to the S N 1 mechanism because the S N 2 mechanism avoids the energtically-expensive carbocation formation step. We consider S N 1 only when S N 2 has been ruled out, or if the conditions obviously favor S N 1.
Amines are generally modest or good nucleophiles.
Good leaving group . Iodide ion is an excellent leaving group because it is highly polarizable. Substitution not occurring at tertiary carbon . In this case, the substitution is occurring at a 1 o carbon. Therefore the reaction will most probably proceed via the S N 2 mechanism.