Predict product B for the following reaction sequence below. 2-methyl-2-butene + water –> A (if any)
A A tertiary alcohol
B A secondary alcohol
C An ester
D A carboxylic Acid
E A ketone
F A aldehyde
The Correct Answer and Explanation is :
The correct answer to this reaction is B: A secondary alcohol.
Explanation:
The reaction sequence provided involves 2-methyl-2-butene reacting with water.
- Starting compound: 2-methyl-2-butene
- The structure of 2-methyl-2-butene is an alkene with the following structure:
[
CH_3-C(=CH_2)-CH_2-CH_3
]
This molecule has a double bond between the second and third carbons, with a methyl group attached to the second carbon.
- Reaction with water (Hydration)
- The reaction is a typical acid-catalyzed hydration of an alkene, where the alkene undergoes an electrophilic addition with water in the presence of an acid (e.g., H₂SO₄).
- In this case, the hydration will follow Markovnikov’s Rule, which states that the proton (H⁺) will add to the carbon of the double bond that has the greater number of hydrogen atoms (the more substituted carbon).
- The alkene 2-methyl-2-butene has the double bond between the second and third carbons. The more substituted carbon (the second carbon) will preferentially bond with the proton from water. The hydroxyl group (-OH) will then add to the carbon with fewer hydrogens (the third carbon).
- Resulting product:
- The product of this reaction will be a secondary alcohol, specifically 2-methyl-2-butanol. The structure of this alcohol is:
[
CH_3-CH(OH)-CH_2-CH_3
]
This is a secondary alcohol because the hydroxyl group (-OH) is attached to a carbon that is connected to two other carbons.
Therefore, the answer is B: A secondary alcohol.
Let me go ahead and generate the image for the reaction mechanism.
Here’s the chemical diagram showing the reaction of 2-methyl-2-butene with water, leading to the formation of 2-methyl-2-butanol, a secondary alcohol. This diagram illustrates the process of Markovnikov addition, where the proton adds to the more substituted carbon of the alkene, resulting in the formation of the alcohol.
Let me know if you’d like more details or have any further questions!
