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

13. Alcohols and Carbonyl Compounds

Nucleophilic Addition

Organic Chemistry

13. Alcohols and Carbonyl Compounds

Nucleophilic Addition

Previous problemNext problem

8:45 minutes

Problem 39a

Textbook Question

Propose a mechanism for the following reactions:
a.

Verified step by step guidance

Step 1: Analyze the starting material and reaction conditions. The starting material is a 2,5-dimethylfuran, a heterocyclic compound with an oxygen atom in the ring. The reaction conditions include HCl, water (H₂O), and heat (Δ), which suggest an acid-catalyzed hydrolysis mechanism.

Step 2: Protonation of the furan ring. Under acidic conditions, the oxygen atom in the furan ring is protonated by HCl, increasing the electrophilicity of the ring and making it more susceptible to nucleophilic attack.

Step 3: Nucleophilic attack by water. Water acts as a nucleophile and attacks the protonated furan ring, leading to the opening of the ring and the formation of an intermediate with hydroxyl groups attached to the carbons.

Step 4: Rearrangement and cleavage. The intermediate undergoes rearrangement and cleavage of bonds, leading to the formation of two carbonyl compounds. The heat (Δ) facilitates this process by providing the energy required for bond breaking and formation.

Step 5: Formation of final products. The reaction yields two ketones: acetone (CH₃COCH₃) and butan-2-one (CH₃CH₂COCH₃), as the final products. These are stabilized by resonance and the absence of further reactive groups under the given conditions.

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.

Reaction Mechanism

A reaction mechanism is a step-by-step description of how a chemical reaction occurs at the molecular level. It outlines the sequence of elementary steps, including bond breaking and formation, and the intermediates formed during the reaction. Understanding the mechanism is crucial for predicting the products and the conditions under which the reaction occurs.

Nucleophiles and Electrophiles

Nucleophiles are species that donate an electron pair to form a chemical bond, while electrophiles are electron-deficient species that accept an electron pair. Identifying these species in a reaction is essential for proposing a mechanism, as it helps to determine the flow of electrons and the formation of new bonds. This concept is fundamental in organic reactions, particularly in substitution and addition reactions.

Transition States and Intermediates

Transition states are high-energy states that occur during the transformation of reactants to products, representing the point of maximum energy along the reaction pathway. Intermediates are species that are formed during the reaction but are not present in the final products. Understanding these concepts is vital for visualizing the energy changes and the stability of different species throughout the reaction mechanism.

Watch next

Master Nucleophilic Addition with a bite sized video explanation from Johnny

Start learning

Related Videos

Related Practice

Textbook Question

Show how you would synthesize each compound, beginning with acetylene and any necessary additional reagents

(c)

(d)

Textbook Question

Within each set of structures, indicate which will react fastest, and which slowest, toward nucleophilic addition in basic conditions.

(c)

Textbook Question

Within each set of structures, indicate which will react fastest, and which slowest, toward nucleophilic addition in basic conditions.

(b)

Textbook Question

Show how you would accomplish the following syntheses.

b. cyclopentanecarbaldehyde → 2-cyclopentyl-2-hydroxyacetic acid

Textbook Question

Predict the product of the following aldehyde and ketone addition reactions.

(b)

Textbook Question

Classify the following nucleophiles as strong, weak, or intermediate. Would you expect each to add to a carbonyl directly or wait for a carbocation to form?

(a)

Textbook Question

Classify the following nucleophiles as strong, weak, or intermediate. Would you expect each to add to a carbonyl directly or wait for a carbocation to form?

(d)

Textbook Question

Based on the analysis you used in Assessment 17.3, which carbonyl would you expect to react most quickly with a nucleophile?

(a)

Show more practices