Question

Question: Draw the structure of each transition state in the two-step mechanism for the reaction.

CH₃CH₂OH + H₂So₄ → CH₃CH=CH₂+ H₂O

Short answer

Answer

The mechanism is shown below.

Step-by-step solution

Step-by-Step Solution Step 1: Dehydration of an alcohol

The reactivity of the dehydration of alcohol depends upon the carbocation’s stability. The first step of the dehydration of alcohol is the formation of a carbocation.

Formation of carbocation

In the first step, the oxygen abstracts a proton from an acid (followed by the removal of water) to form carbocation, as shown below.

Formation of carbocation

1,2 hydride shift and product formation

In the second step, the 1,2-hydride shift takes place. The product is formed by the deprotonation, as shown below.

Formation of the product