Textbook Question
Which of the following alkenes would you expect to react fastest with HBr in each pair?
(b)
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Ch. 8 - Alkenes I: Properties and Electrophilic Additions
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471
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Table of contents
- Ch. 2 - General Chemistry Translated: Finding the Electrons114
- Ch. 3 - Alkanes and Cycloalkanes: Properties and Conformational Analysis109
- Ch. 4 - Acids and Bases: Electron Flow144
- Ch. 5 - Chemical Reaction Analysis: Thermodynamics and Kinetics118
- Ch. 6 - Stereoisomerism: Arrangement of Atoms in Space112
- Ch. 7 - Principles of Green (Organic) Chemistry3
- Ch. 8 - Alkenes I: Properties and Electrophilic Additions158
- Ch. 9 - Alkenes II: Oxidation and Reduction150
- Ch. 10 - Alkynes: Electrophilic Addition and Redox Reactions101
- Ch. 11 - Properties and Synthesis of Alkyl Halides: Radical Reactions108
- Ch. 12 - Substitution and Elimination: Reactions of Haloalkanes172
- Ch. 13 - Alcohols, Ethers and Related Compounds: Substitution and Elimination239
- Ch. 14 - Structural Identification I: Infrared Spectroscopy and Mass Spectrometry54
- Ch. 15 - Structural Identification II: Nuclear Magnetic Resonance Spectroscopy93
- Ch. 16 - Metals in Organic Chemistry48
- Ch. 17 - Carbonyl Addition Reactions: Aldehydes and Ketones45
- Ch. 18 - Nucleophilic Acyl Substitution I: Carboxylic Acids18
- Ch. 19 - Nucleophilic Acyl Substitution II: Carboxylic Acid Derivatives39
- Ch. 20 - Enolates: Carbonyl Addition and Substitution13
- Ch. 21 - Conjugated Systems I: Stability and Addition Reactions56
- Ch. 22 - Conjugated Systems II: Pericyclic Reactions54
- Ch. 23 - Benzene I: Aromatic Stability and Substitution Reactions64
- Ch. 24 - Benzene II: Reactions Influenced by the Aromatic Ring62
- Ch. 25 - Amines: Structure, Reactions, and Synthesis27
- Ch. 26 - Amino Acids, Proteins, and Peptide Synthesis9
- Ch. 27 - Carbohydrates, Nucleic Acids, and Lipids54
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471Not the one you use?Change textbook
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Mullins 1st EditionCh. 8 - Alkenes I: Properties and Electrophilic AdditionsProblem 61k(ii)
Mullins 1st EditionCh. 8 - Alkenes I: Properties and Electrophilic AdditionsProblem 61k(ii)Chapter 7, Problem 61k(ii)
Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions:(ii) HCl
(k) 
Verified step by step guidance1
Identify the type of reaction: The reaction of an alkene with HCl is an electrophilic addition reaction. The π-electrons of the alkene act as a nucleophile and react with the electrophilic hydrogen (H⁺) from HCl.
Determine the regioselectivity: Use Markovnikov's rule to predict the major product. According to this rule, the hydrogen atom (H⁺) will add to the carbon of the double bond that has more hydrogen atoms already attached, while the chlorine (Cl⁻) will add to the carbon with fewer hydrogen atoms.
Draw the carbocation intermediate: After the addition of H⁺ to the alkene, a carbocation intermediate is formed. Ensure that you consider the stability of the carbocation. If possible, rearrangements (e.g., hydride or alkyl shifts) may occur to form a more stable carbocation.
Add the nucleophile: The chloride ion (Cl⁻) will attack the positively charged carbocation, forming the final product. Ensure that you show the correct connectivity in the product structure.
Verify the stereochemistry (if applicable): If the reaction generates a chiral center, consider whether the product will be a racemic mixture or if stereoselectivity is involved. For simple alkenes, this step may not be necessary.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Electrophilic Addition
Electrophilic addition is a fundamental reaction mechanism in organic chemistry where an electrophile reacts with a nucleophile, typically involving alkenes. In the presence of HCl, the double bond of the alkene acts as a nucleophile, attacking the electrophilic hydrogen atom of HCl, leading to the formation of a carbocation intermediate. This process is crucial for predicting the products of alkene reactions.
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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 regioselectivity of the reaction, guiding the formation of the more stable carbocation and ultimately the major product of the reaction when alkenes react with HCl.
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Carbocation Stability
Carbocation stability is a key concept in organic chemistry that refers to the relative stability of positively charged carbon species. 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, influencing the product distribution in reactions involving alkenes and HCl.
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Related Practice
Textbook Question
Cyclooctene is one of the smaller rings that can form a trans alkene. Would you expect cis-cyclooctene or trans-cyclooctene to react more quickly in an acid-catalyzed hydration reaction?
Textbook Question
Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions: (iii) HBr, H2O2
(k)
Textbook Question
Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions: (iv) H2SO4 , H2O
(k)
11
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Textbook Question
Which of the following cycloalkanes would you expect to produce the least heat upon combustion when measured per CH2? Explain your answer.
1
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Textbook Question
Predict the product(s) that would result when the alkenes shown here are allowed to react under the following conditions: (i) HBr
(k)
1
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