1. Regioselectivity of E2 reactions
Section 8.7

2. 8.7 Regioselectivity of E2
If there are multiple reactive sites or regions on a molecule, multiple products are possible
In elimination reactions, there are often different β sites that could be deprotonated to yield different alkenes
What is the relationship between the alkene products?
Regioselectivity occurs when one constitutional product is formed predominantly over the other
Zaitsev product
Hofmann product
Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.
Klein, Organic Chemistry 2e

3. 8.7 Regioselectivity of E2
The identity of the base can affect the regioselesctivity
Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.
Klein, Organic Chemistry 2e

4. 8.7 Regioselectivity of E2
Why does the Zaitsev product predominate when a base that is NOT sterically hindered is used?
Is the Zaitsev product kinetically favored, thermodynamically favored, or both?
Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.
Klein, Organic Chemistry 2e

5. 8.7 Regioselectivity of E2
Why does a sterically hindered base favor the Hofmann product?
Sterically hindered bases (sometimes called non-nucleophilic) are useful in many reactions
Practice with SkillBuilder 8.5
Copyright © 2015 John Wiley & Sons, Inc. All rights reserved.
Klein, Organic Chemistry 2e