1. CH 6-4 SN1 Reaction – Part I
SN1: “Substitution….Nucleophilic….Unimolecular (RLS)”
Rate = k [substrate] (1st order reaction)

2. The SN1 Mechanism
Carbocation Mechanism. “Ionization” of the substrate occurs in the 1st Step:
RLS
(1)
intermediate
sp2; trigonal planar

3. The SN1 Mechanism
In the 2nd Step the nucleophile “grabs” the Carbocation forming a new bond.
(2)
intermediate
If you add together Step you must get the Net equation:

4. The SN1 Reaction
Energy Diagram; minimum of two-steps:
(RLS)

5. The SN1 Transition State: RLS only “Polar” T.S. “unimolecular”