In an E2 elimination reaction, what is the role of the base?
Practice Questions
Q1
In an E2 elimination reaction, what is the role of the base?
To donate a proton
To stabilize the carbocation
To act as a leaving group
To form a cyclic intermediate
Questions & Step-by-Step Solutions
In an E2 elimination reaction, what is the role of the base?
Step 1: Identify the E2 elimination reaction, which involves a substrate with a leaving group and adjacent hydrogen atoms (β-hydrogens).
Step 2: Recognize that a base is a substance that can accept protons (H+ ions).
Step 3: In the E2 reaction, the base approaches the β-carbon, which is the carbon adjacent to the one with the leaving group.
Step 4: The base abstracts (removes) a proton from the β-carbon, creating a negative charge on the β-carbon.
Step 5: As the base removes the proton, the leaving group (attached to the α-carbon) departs, resulting in the formation of a double bond between the α-carbon and the β-carbon.
Step 6: The overall result is the formation of an alkene (a compound with a double bond) from the original substrate.
