Elimination Reactions
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E2 mechanism with
the alkoxide removing the hydrogen and the bromine
departing in a concerted transition state involving a
trans- elimination. Also recall that the most
highly substituted alkene will generally be formed.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E1 mechanism with
the toluenesulfonate departing, followed by rapid removal
of the hydrogen. Recall that rearrangements are
generally observed in E1 reactions and the most
highly substituted alkene is generally formed.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E2 mechanism with
the alkoxide removing the hydrogen and the bromine
departing in a concerted transition state involving a
trans- elimination. The most highly substituted
alkene is not formed in this reaction in favor of the
conjugated alkene. Removal of the hydrogen from the
tertiary center is also slower than the removal of the
hydrogen from the CH2 group.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E1 mechanism with
the bromine departing, followed by rapid removal of the
hydrogen. Recall that rearrangements are generally
observed in E1 reactions and the most highly
substituted alkene is generally formed.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E1 mechanism with
the toluenesulfonate departing, followed by rapid removal
of the hydrogen. Recall that rearrangements are
generally observed in E1 reactions and the most
highly substituted alkene is generally formed.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E2 mechanism with
the alkoxide removing the hydrogen and the bromine
departing in a concerted transition state involving a
trans- elimination. Also recall that the most
highly substituted alkene will generally be formed.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E1 mechanism with
the bromine departing, followed by rapid removal of the
hydrogen. Recall that rearrangements are generally
observed in E1 reactions and the most highly
substituted alkene is generally formed. Although a
secondary center can also undergo E2 elimination, the
hydrogen on the tertiary carbon would be removed more
slowly than the hydrogen on the adjacent secondary center.
Thus, an E2 mechanism would most likely yield
4-methyl-2-pentene.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E1 mechanism with
the bromine departing, followed by rapid removal of the
hydrogen. Recall that rearrangements are generally
observed in E1 reactions and the most highly
substituted alkene is generally formed. Although a
secondary center can also undergo E2 elimination, the
hydrogen on the tertiary carbon would be removed more
slowly than the hydrogen on the adjacent secondary center.
Thus, an E2 mechanism would most likely yield
3-methylcyclopentene.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below:
This reaction will most likely follow an E1 mechanism with
the bromine departing, followed by rapid removal of the
hydrogen. Recall that rearrangements are generally
observed in E1 reactions and the most highly
substituted alkene is generally formed.
Using the drawing pallet on the right, draw the structure
of the major organic product for the reaction shown below.
You should assume than an E2 mechanism is observed.
Because this reaction follows an E2 mechanism, the alkoxide
will remove a hydrogen which is trans- the bromine
in a concerted transition state (a trans-
elimination). In this reaction, the most highly
substituted alkene is not formed because the hydrogen on
the tertiary center is not trans- to the bromine.
Elinination from the secondary position (where there is a
trans- hydrogen) gives the final product. An E1
mechanism would have given the alternate product,
1-methylcyclohexene.
That is correct!
Sorry, that is not correct. You should modify your
structures and try again. If cis-trans-
stereochemistry is required, please make sure you have
drawn the appropriate isomer using the "wedge bonds".
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