16.4 Electrophilic Addition to Conjugated Dienes
PRE-HEALTH PREP
Kinetic Product
The Kinetic Product is the product formed with the lowest activation energy (most stable transition state).
-Focus on the most stable resonance contributor of the carbocation intermediate.
-It is the major product at lower temperatures and shorter reaction times.
Thermodynamic Product
The Thermodynamic Product is the most stable product (i.e. most substituted alkene in this context).
-It is the major product at higher temperatures and longer reaction times.
Kinetic Product
The Kinetic Product is the product formed with the lowest activation energy (most stable transition state).
-Focus on the most stable resonance contributor of the carbocation intermediate.
-It is the major product at lower temperatures and shorter reaction times.
| PREDICTING THE PRODUCTS FOR ADDITION REACTIONS TO CONJUGATED DIENES |
|---|
| 1. Start by identifying the resonance-stabilized carbocation intermediates. Discard/ignore the others. |
| 2. Select the more stable carbocation (shares the positive charge on the more substituted carbon atoms). |
| 3. Draw both possible products when the nucleophile adds to the two carbon that share the positive charge. |
| 4. The product resulting from the nucleophile adding to the more substituted carbon is the kinetic product. |
| 5. The product with the more substituted pi bond is the thermodynamic product. |
Predict both the kinetic and thermodynamic products of the following reaction.
Pericyclic Reactions
1. Cycloaddition Reactions
2. Electrocylic Reactions
3. Sigmatropic Rearrangements
