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

10. Addition Reactions

Alkyne Oxidative Cleavage

Organic Chemistry

10. Addition Reactions

Alkyne Oxidative Cleavage

Previous problemNext problem

5:15 minutes

Problem 23d

Textbook Question

Predict the product(s) you would expect from treatment of each compound with (1) dilute, neutral KMnO₄ and (2) warm basic KMnO₄, then dilute acid.
(d) 2-methylhex-3-yne

Verified step by step guidance

Step 1: Understand the reactivity of the alkyne (2-methylhex-3-yne) with KMnO4. Neutral KMnO4 (dilute) is a mild oxidizing agent that adds hydroxyl groups across the triple bond, forming a diol. Warm, basic KMnO4 followed by acid is a stronger oxidizing agent that cleaves the triple bond, producing carboxylic acids.

Step 2: For reaction with dilute, neutral KMnO4, identify the triple bond in 2-methylhex-3-yne. The triple bond is between carbons 3 and 4. Neutral KMnO4 will add hydroxyl groups (-OH) to both carbons of the triple bond, resulting in a vicinal diol (a compound with two hydroxyl groups on adjacent carbons).

Step 3: For reaction with warm, basic KMnO4 followed by acid, the triple bond undergoes oxidative cleavage. This means the triple bond is broken, and each carbon of the triple bond is oxidized to a carboxylic acid. Identify the groups attached to carbons 3 and 4 to determine the resulting carboxylic acids.

Step 4: Analyze the structure of 2-methylhex-3-yne. Carbon 3 is bonded to a methyl group and a hydrogen, while carbon 4 is bonded to a propyl group and a hydrogen. Upon oxidative cleavage, carbon 3 will form acetic acid (CH3COOH), and carbon 4 will form butanoic acid (CH3CH2CH2COOH).

Step 5: Summarize the products. For dilute, neutral KMnO4, the product is a vicinal diol. For warm, basic KMnO4 followed by acid, the products are acetic acid and butanoic acid. Ensure to draw the structures of the products for clarity.

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.

Oxidation Reactions

Oxidation reactions involve the loss of electrons or an increase in oxidation state by a molecule. In organic chemistry, these reactions often lead to the formation of alcohols, ketones, or carboxylic acids. Understanding how different oxidizing agents, like KMnO4, interact with various functional groups is crucial for predicting the products of these reactions.

KMnO4 as an Oxidizing Agent

Potassium permanganate (KMnO4) is a strong oxidizing agent used in organic synthesis. In dilute, neutral conditions, it typically oxidizes alkynes to form cis-diol products, while in warm basic conditions followed by acid treatment, it can cleave alkynes to yield carboxylic acids. Recognizing the conditions under which KMnO4 operates helps in predicting the outcome of reactions.

Alkyne Reactivity

Alkynes, characterized by carbon-carbon triple bonds, exhibit unique reactivity patterns compared to alkenes and alkanes. They can undergo various reactions, including oxidation, which can lead to the formation of different functional groups. Understanding the structure and reactivity of 2-methylhex-3-yne is essential for predicting the products when treated with KMnO4.

Watch next

Master General features of alkyne cleavage. with a bite sized video explanation from Johnny

Start learning

Related Videos

Related Practice

Textbook Question

Oxidative cleavages can help to determine the positions of the triple bonds in alkynes.

(a) An unknown alkyne undergoes oxidative cleavage to give adipic acid and two equivalents of acetic acid. Propose a structure for the alkyne.

Textbook Question

Oxidative cleavages can help to determine the positions of the triple bonds in alkynes.

(b) An unknown alkyne undergoes oxidative cleavage to give the following triacid plus one equivalent of propionic acid. Propose a structure for the alkyne.

Textbook Question

Using cyclooctyne as your starting material, show how you would synthesize the following compounds. (Once you have shown how to synthesize a compound, you may use it as the starting material in any later parts of this problem.)

(g) cyclooctane-1,2-dione

Textbook Question

(i)

Textbook Question

Predict the product(s) you would expect from treatment of each compound with (1) dilute, neutral KMnO₄ and (2) warm basic KMnO₄, then dilute acid.

(e) cyclodecyne

Textbook Question

Deduce the structure of each compound from the information given. All unknowns in this problem have molecular formula C₈H₁₂.

(a) Upon catalytic hydrogenation, unknown W gives cyclooctane. Ozonolysis of W, followed by reduction with dimethyl sulfide, gives octanedioic acid, HOOC–(CH₂)₆–COOH. Draw the structure of W.

Textbook Question

Predict the product(s) you would expect from treatment of each compound with (1) dilute, neutral KMnO4 and (2) warm basic KMnO4, then dilute acid.

(b) hex-2-yne

Textbook Question

Predict the product(s) you would expect from treatment of each compound with (1) dilute, neutral KMnO₄ and (2) warm basic KMnO₄, then dilute acid.

(a) hex-1-yne

Show more practices

Download the Mobile app

Privacy

Do not sell my personal information

Accessibility

Patent notice

Sitemap

Predict the product(s) you would expect from treatment of each compound with (1) dilute, neutral KMnO4 and (2) warm basic KMnO4, then dilute acid.(d) 2-methylhex-3-yne

Key Concepts

Oxidation Reactions

KMnO4 as an Oxidizing Agent

Alkyne Reactivity

Watch next

Predict the product(s) you would expect from treatment of each compound with (1) dilute, neutral KMnO₄ and (2) warm basic KMnO₄, then dilute acid.
(d) 2-methylhex-3-yne