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

3. Acids and Bases

Reaction Mechanism

Organic Chemistry

3. Acids and Bases

Reaction Mechanism

Previous problemNext problem

5:25 minutes

Problem 57c

Textbook Question

Identify the electrophile and the nucleophile in each of the following reaction steps and then draw curved arrows to illustrate the bond-making and bondbreaking processes.
c.

Verified step by step guidance

Step 1: Identify the electrophile and nucleophile in the reaction. The electrophile is BH₃ (borane) because it has an empty p-orbital and can accept electrons. The nucleophile is CH₃CH=CH₂ (propene) because the π-electrons in the double bond can donate electrons.

Step 2: Analyze the bond-making and bond-breaking process. The π-electrons from the double bond in propene attack the boron atom in BH₃, forming a new bond between the boron and one of the carbon atoms in the double bond.

Step 3: Draw curved arrows to represent the electron movement. One curved arrow should originate from the π-electrons of the double bond and point toward the boron atom in BH₃, indicating the formation of the new bond.

Step 4: Note the regioselectivity of the reaction. In hydroboration, the boron atom typically attaches to the less substituted carbon of the double bond due to steric and electronic factors.

Step 5: The product of the reaction is CH₃CH₂CH₂BH₂, where the double bond is broken, and a single bond is formed between boron and the less substituted carbon atom. Ensure the curved arrows accurately depict the electron flow leading to this product.

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.

Electrophiles

Electrophiles are species that accept electrons during a chemical reaction. They are typically positively charged or neutral molecules with an electron-deficient atom, making them attractive to nucleophiles. In the given reaction, borane (BH3) acts as the electrophile, as it can accept a pair of electrons from the alkene.

Nucleophiles

Nucleophiles are electron-rich species that donate a pair of electrons to form a chemical bond. They are usually negatively charged or neutral molecules with a lone pair of electrons. In this reaction, the alkene (CH3CH=CH2) serves as the nucleophile, providing electrons to bond with the electrophile, borane.

Curved Arrows in Mechanisms

Curved arrows are used in organic chemistry to illustrate the movement of electrons during chemical reactions. The tail of the arrow indicates the electron source (where the electrons are coming from), while the head points to the electron destination (where the electrons are going). In this reaction, curved arrows would show the electron donation from the alkene to borane, indicating bond formation and breaking.

Watch next

Master How to tell if a molecule will be reactive or not. with a bite sized video explanation from Johnny

Start learning

Related Videos

Related Practice

Textbook Question

The following reaction steps are shown using conventional electron pushing. (b) Use the bouncing arrow formalism to illustrate the formation of only the product shown.

(a)

Textbook Question

For the following acid–base pairs, (v) show a mechanism for the reaction;

(e)

Textbook Question

Identify the electrophile and the nucleophile in each of the following reaction steps and then draw curved arrows to illustrate the bond-making and bondbreaking processes.

Textbook Question

Identify the electrophile and the nucleophile in each of the following reaction steps and then draw curved arrows to illustrate the bond-making and bondbreaking processes.

Textbook Question

Label the reactants in these acid–base reactions as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions.

Textbook Question

In each reaction, label the reactants as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions. Draw any nonbonding electrons to show how they participate in the reactions.

Textbook Question

Each of these compounds can react as a nucleophile. In each case, use curved arrows to show how the nucleophile would react with the strong electrophile BF₃.

(e) CH₃CH₂OH

Textbook Question

Each of these compounds can react as a nucleophile. In each case, use curved arrows to show how the nucleophile would react with the strong electrophile BF₃.

(f) (CH₃)₂S

Show more practices

Download the Mobile app

Privacy

Do not sell my personal information

Accessibility

Patent notice

Sitemap

Identify the electrophile and the nucleophile in each of the following reaction steps and then draw curved arrows to illustrate the bond-making and bondbreaking processes.c.

Key Concepts

Electrophiles

Nucleophiles

Curved Arrows in Mechanisms

Watch next

Identify the electrophile and the nucleophile in each of the following reaction steps and then draw curved arrows to illustrate the bond-making and bondbreaking processes.
c.