Textbook Question
What are the products of the following reactions?
c.
1055
views
Ch. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of Benzene
Bruice8th EditionOrganic ChemistryISBN: 9780135213711
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch. 1 - Remembering General Chemistry: Electronic Structure and Bonding (Part 1)31
- Ch. 1 - Remembering General Chemistry: Electronic Structure and Bonding (Part 2)65
- Ch. 2 - Acids and Bases: Central to Understanding Organic Chemistry84
- Ch. 3 - An Introduction to Organic Compounds:Nomenclature, Physical Properties, and Structure183
- Ch. 4 - Isomers: The Arrangement of Atoms in Space121
- Ch. 5 - Alkenes: Structure, Nomenclature, and an Introduction to Reactivity • Thermodynamics and Kinetics83
- Ch. 6 - The Reactions of Alkenes • The Stereochemistry of Addition Reactions175
- Ch. 7 - The Reactions of Alkynes • An Introduction to Multistep Synthesis119
- Ch. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of Benzene148
- Ch. 9 - Substitution and Elimination Reactions of Alkyl Halides212
- Ch. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing Compounds131
- Ch. 11 - Organometallic Compounds60
- Ch. 12 - Radicals90
- Ch. 13 - Mass Spectrometry; Infrared Spectroscopy; UV/Vis Spectroscopy62
- Ch. 14 - NMR Spectroscopy95
- Ch. 15 - Reactions of Carboxylic Acids and Carboxylic Acid Derivatives123
- Ch. 16 - Reactions of Aldehydes and Ketones • More Reactions of Carboxylic Acid Derivatives141
- Ch. 17 - Reactions at the Alpha-Carbon101
- Ch. 18 - Reactions of Benzene and Substituted Benzenes144
- Ch. 19 - More About Amines • Reactions of Heterocyclic Compounds49
- Ch. 20 - The Organic Chemistry of Carbohydrates80
- Ch. 21 - Amino Acids, Peptides, and Proteins57
- Ch. 22 - Catalysis in Organic Reactions and in Enzymatic Reactions35
- Ch. 23 - The Organic Chemistry of the Coenzymes—Compounds Derived from Vitamins1
- Ch. 28 - Pericyclic Reactions58
All textbooks
Bruice 8th EditionCh. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of BenzeneProblem 37a
Bruice 8th EditionCh. 8 - Delocalized Electrons: Their Effect on Stability, pKa, and the Products of a Reaction • Aromaticity and Electronic Effects: An Introduction to the Reactions of BenzeneProblem 37aChapter 9, Problem 37a
What are the major 1,2- and 1,4-addition products of the following reaction? Indicate the kinetic and the thermodynamic products.
a. 
Verified step by step guidance1
Analyze the given structure: The molecule is a conjugated diene, specifically 2-methyl-1,3-cyclopentadiene. Conjugated dienes are capable of undergoing 1,2- and 1,4-addition reactions when reacted with electrophiles.
Understand the reaction mechanism: In the presence of an electrophile (e.g., HBr), the double bonds in the conjugated diene can react to form carbocation intermediates. The electrophile will add to one of the double bonds, creating a carbocation at the adjacent carbon.
Determine the 1,2-addition product: The electrophile adds to the first double bond, and the nucleophile (e.g., Br⁻) attaches to the carbocation formed on the adjacent carbon. This product is typically the kinetic product because it forms faster due to proximity of the nucleophile to the carbocation.
Determine the 1,4-addition product: The electrophile adds to the first double bond, but the carbocation rearranges to the fourth carbon in the conjugated system. The nucleophile then attaches to this rearranged carbocation. This product is typically the thermodynamic product because it is more stable due to conjugation.
Compare kinetic and thermodynamic products: The kinetic product (1,2-addition) forms faster at lower temperatures, while the thermodynamic product (1,4-addition) is favored at higher temperatures due to its greater stability. Analyze the reaction conditions to predict which product will dominate.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
7mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
1,2- and 1,4-Addition Reactions
1,2- and 1,4-addition reactions refer to the ways in which reagents can add to conjugated systems, such as alkenes. In 1,2-addition, the reagent adds to the first and second carbon atoms of the double bond, while in 1,4-addition, it adds to the first and fourth carbon atoms. These pathways lead to different products, which can have distinct stability and reactivity.
Recommended video:
1:42
Addition Reactions of Furan Concept 1
Kinetic vs. Thermodynamic Products
Kinetic and thermodynamic products arise from different reaction conditions and pathways. Kinetic products are formed faster and are typically less stable, while thermodynamic products are more stable and form more slowly. Understanding the conditions that favor one over the other, such as temperature and reaction time, is crucial for predicting the outcome of addition reactions.
Recommended video:
Guided course
08:51Kinetic vs. Thermodynamic Control
Conjugated Systems
Conjugated systems are compounds with alternating single and double bonds, which allow for delocalization of electrons. This delocalization stabilizes the molecule and influences its reactivity. In the context of addition reactions, the presence of conjugation can affect the regioselectivity and the stability of the products formed, making it essential to consider when analyzing reaction outcomes.
Recommended video:
Guided course
03:27Conjugated states
Related Practice
Textbook Question
What are the major 1,2- and 1,4-addition products of the following reaction? Indicate the kinetic and the thermodynamic products.
b.
1247
views
Textbook Question
What are the products of the following reactions, assuming that one equivalent of each reagent is used in each reaction? Disregard stereoisomers.
b.
1343
views
Textbook Question
What are the products of the following reactions, assuming that one equivalent of each reagent is used in each reaction? Disregard stereoisomers.
a.
701
views
Textbook Question
What are the products of the following reactions?
d.
830
views
Textbook Question
A student wanted to know whether the greater proximity of the nucleophile to the C-2 carbon in the transition state is what causes the 1,2-addition product to be formed faster when 1,3-butadiene reacts with HCl. Therefore, she decided to investigate the reaction of 2-methyl-1,3-cyclohexadiene with HCl. Her friend told her that she should use 1-methyl-1,3-cyclohexadiene instead. Should she follow her friend's advice?
1114
views