Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

9. Alkenes and Alkynes

Dehydration Reaction

Organic Chemistry

9. Alkenes and Alkynes

Dehydration Reaction

Previous problemNext problem

2:05 minutes

Problem 41b

Textbook Question

Identify the alcohol(s) that would produce the following alkenes under the given conditions.
(b)

Verified step by step guidance

Step 1: Recognize the reaction type. The given reaction involves the dehydration of alcohols using sulfuric acid (H₂SO₄) as a catalyst. Dehydration reactions typically result in the formation of alkenes by eliminating a water molecule from the alcohol.

Step 2: Analyze the structure of the alkene product. The product shown is 2-methyl-2-pentene, which has a double bond between the second and third carbon atoms in a six-carbon chain with a methyl group attached to the second carbon.

Step 3: Determine the alcohol precursor. To form this alkene, the alcohol precursor must have a hydroxyl (-OH) group attached to the carbon that will lose a hydrogen during the elimination process. This is typically the carbon adjacent to the double bond in the product.

Step 4: Apply Zaitsev's rule. Zaitsev's rule states that the more substituted alkene is favored during elimination. Therefore, the alcohol precursor is likely 2-methyl-2-pentanol, as dehydration of this alcohol would lead to the formation of the most stable, highly substituted alkene.

Step 5: Consider alternative alcohols. Another possible alcohol precursor could be 2-methyl-3-pentanol, which could also undergo dehydration to form the same alkene product under acidic conditions. Both alcohols are valid precursors for the given alkene.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Alcohols and Alkenes

Alcohols are organic compounds containing one or more hydroxyl (-OH) groups, while alkenes are hydrocarbons that contain at least one carbon-carbon double bond. The conversion of alcohols to alkenes typically involves dehydration, where water is removed, leading to the formation of a double bond. Understanding the structure of both alcohols and alkenes is crucial for predicting the products of such reactions.

Dehydration Reaction

A dehydration reaction is a chemical process where a water molecule is removed from a compound, often resulting in the formation of a double bond. In the context of alcohols, this reaction can be catalyzed by acids and typically occurs under heat. Recognizing the conditions that favor dehydration, such as temperature and the presence of catalysts, is essential for determining which alcohols can yield specific alkenes.

Regioselectivity and Zaitsev's Rule

Regioselectivity refers to the preference of a chemical reaction to yield one structural isomer over others. Zaitsev's Rule states that in elimination reactions, the more substituted alkene is typically the major product. This principle helps predict which alkenes will form from specific alcohols during dehydration, guiding the identification of the correct alcohols that lead to the desired alkenes.

Watch next

Master General features of acid-catalyzed dehydration. with a bite sized video explanation from Johnny

Start learning

Identify the alcohol(s) that would produce the following alkenes under the given conditions.(b)

Key Concepts

Alcohols and Alkenes

Dehydration Reaction

Regioselectivity and Zaitsev's Rule

Watch next

Identify the alcohol(s) that would produce the following alkenes under the given conditions.
(b)