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

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5:02 minutes

Problem 32a

Textbook Question

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

Verified step by step guidance

Step 1: Analyze the reactants. The molecule H₃CC≡CH with the positively charged iodine (I⁺) is the electrophile because it has an electron-deficient iodine atom. The negatively charged iodide ion (I⁻) is the nucleophile because it has a lone pair of electrons and is electron-rich.

Step 2: Identify the interaction between the electrophile and nucleophile. The nucleophile (I⁻) will attack the electrophile (I⁺) to form a new bond.

Step 3: Draw the curved arrow to represent the bond-making process. The curved arrow should start from the lone pair of electrons on the nucleophile (I⁻) and point toward the positively charged iodine atom (I⁺) in the electrophile.

Step 4: Illustrate the bond-breaking process. The bond between the positively charged iodine atom (I⁺) and the carbon atom in the electrophile will break, transferring the electrons to the carbon atom. Draw a curved arrow starting from the bond and pointing toward the carbon atom.

Step 5: Confirm the product structure. The final product will show the iodine atom (I⁻) bonded to the carbon atom, and the triple bond remains intact. Ensure the lone pairs on iodine are correctly represented in the product structure.

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Key Concepts

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

Electrophiles

Electrophiles are species that accept electron pairs from nucleophiles during chemical reactions. They are typically positively charged or neutral molecules with an electron-deficient atom, making them attractive to electron-rich species. In the provided reaction, the positively charged carbon in the alkene acts as the electrophile, seeking electrons to form new bonds.

Nucleophiles

Nucleophiles are electron-rich species that donate an electron pair to electrophiles in a chemical reaction. They can be negatively charged ions or neutral molecules with lone pairs of electrons. In the reaction shown, the negatively charged species (likely a carbanion or similar) acts as the nucleophile, attacking the electrophilic carbon to form a new bond.

Curved Arrows in Mechanisms

Curved arrows are used in organic chemistry to illustrate the movement of electron pairs during bond-making and bond-breaking processes. 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 the reaction, curved arrows will show how the nucleophile donates electrons to the electrophile and how bonds are formed or broken.

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