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

Hydrohalogenation

Organic Chemistry

10. Addition Reactions

Hydrohalogenation

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1:17 minutes

Problem 80b

Textbook Question

Propose a mechanism for each of the following reactions:
b.

Verified step by step guidance

Step 1: Identify the type of reaction. This is an electrophilic addition reaction where HCl adds across the double bond of the alkene.

Step 2: Protonation of the alkene. The π-electrons of the double bond attack the hydrogen atom of HCl, leading to the formation of a carbocation intermediate. The more stable carbocation will form, which in this case is the tertiary carbocation due to hyperconjugation and inductive effects.

Step 3: Formation of the carbocation. The double bond breaks, and the hydrogen from HCl attaches to the less substituted carbon of the double bond, leaving the more substituted carbon as the carbocation.

Step 4: Nucleophilic attack by the chloride ion. The chloride ion (Cl⁻) attacks the positively charged carbocation, forming a new bond and resulting in the final product.

Step 5: Verify the product. The final product is 2-chloro-2-methylpropane, where the chlorine atom is attached to the tertiary carbon.

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Key Concepts

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

Electrophilic Addition Reactions

Electrophilic addition reactions involve the addition of an electrophile to a nucleophile, typically across a double bond. In the context of alkenes, the π bond acts as a nucleophile, attacking an electrophile, which leads to the formation of a more stable carbocation intermediate. This mechanism is crucial for understanding how alkenes react with acids and halogens.

Carbocation Stability

Carbocation stability is a key concept in organic chemistry, as the stability of the carbocation intermediate influences the reaction pathway. Carbocations are classified as primary, secondary, or tertiary based on the number of alkyl groups attached to the positively charged carbon. Tertiary carbocations are the most stable due to hyperconjugation and inductive effects, which play a significant role in determining the product of electrophilic addition reactions.

Markovnikov's Rule

Markovnikov's Rule states that in the addition of HX (where X is a halogen) to an alkene, the hydrogen atom will attach to the carbon with the greater number of hydrogen atoms already attached. This rule helps predict the major product of electrophilic addition reactions, as it accounts for the formation of the more stable carbocation intermediate, guiding the regioselectivity of the reaction.