Question #e1140
1 Answer
The third step in the Baeyer Villiger oxidation is the rate determining step because it involves the cleavage of a covalent bond.
Approximate rate constants for the steps are:
- Step 1 =
10^4104 to10^9 " L·mol"^-1"s"^(-1)109 L⋅mol−1s−1 - Step 2 =
10^10 " L·mol"^-1"s"^(-1)1010 L⋅mol−1s−1 - Step 3 =
10^(-6)" s"^(-1)10−6 s−1 - Step 4 =
10^4104 to10^9 " L·mol"^-1"s"^(-1)109 L⋅mol−1s−1
Since no reaction can go faster than its slowest step, Step 3 is the rate determining step.
Step 1 is a simple OH proton transfer.
Such reactions are fast, with rate constants ranging from
Step 2 is the addition of an anion to a cation to form a neutral molecule.
These reactions are also very fast, with rate constants of about
Step 3 is the decomposition of the acyl peroxide (the Criegee intermediate).
This involves the cleavage of a covalent O-O bond.
This is a much slower process. For example, the rate constant for the decomposition of t-butyl peroxyacetate is about
Step 4 is another rapid proton transfer.
