Textbook Question
What product is obtained from the reaction of each of the following alcohols with
a. H2CrO4?
1. 3-pentanol
2. 1-pentanol
3. 2-methyl-2-pentanol
Ch. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing Compounds
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. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing CompoundsProblem 20
Bruice 8th EditionCh. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing CompoundsProblem 20Chapter 11, Problem 20
If the compound shown in the margin is heated in the presence of H2SO4,
a. what constitutional isomer would be formed in greatest yield?
b. what stereoisomer would be formed in greater yield?
Verified step by step guidance1
Analyze the given compound: The structure shows a cyclohexane ring with a secondary alcohol (-OH group) attached to a carbon that also has a methyl group (-CH3). This is a secondary alcohol.
Understand the reaction conditions: Heating in the presence of H2SO4 (sulfuric acid) typically leads to an elimination reaction (E1 mechanism) where the alcohol is converted into an alkene via dehydration.
Determine the major constitutional isomer: The E1 mechanism proceeds through the formation of a carbocation intermediate. The most stable carbocation will form, which in this case is the secondary carbocation. The elimination will follow Zaitsev's rule, favoring the formation of the more substituted alkene. This means the double bond will likely form between the carbon bearing the -OH group and the adjacent carbon in the ring.
Consider stereoisomer formation: The elimination reaction can produce stereoisomers (E/Z isomers) depending on the spatial arrangement of substituents around the double bond. The major stereoisomer will be the one with the substituents in the most stable configuration, typically the E-isomer (trans configuration) due to reduced steric hindrance.
Summarize the expected products: The major constitutional isomer will be the more substituted alkene formed via Zaitsev's rule, and the major stereoisomer will be the E-isomer due to its stability.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
4mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Dehydration Reactions
Dehydration reactions involve the removal of a water molecule from a compound, typically resulting in the formation of a double bond. In organic chemistry, this process is common for alcohols when heated in the presence of an acid, such as sulfuric acid (H2SO4). The reaction can lead to the formation of alkenes, which can have multiple structural isomers depending on the position of the double bond.
Recommended video:
Guided course
01:23
General Reaction of Dehydration with POCl3
Constitutional Isomers
Constitutional isomers are compounds that have the same molecular formula but differ in the connectivity of their atoms. This means that the atoms are arranged in different ways, leading to distinct compounds with unique properties. In the context of dehydration reactions, the formation of different constitutional isomers can occur based on how the double bond is formed during the elimination of water.
Recommended video:
Guided course
01:10What is a constitutional isomer?
Stereoisomers
Stereoisomers are compounds that have the same molecular formula and connectivity of atoms but differ in the spatial arrangement of their atoms. This can lead to different physical and chemical properties. In dehydration reactions, stereoisomer formation is influenced by the orientation of substituents around the double bond, which can result in cis/trans or E/Z isomers depending on the substituents' positions.
Recommended video:
Guided course
01:58Determining when molecules are stereoisomers.
Related Practice
Textbook Question
What alcohol would you treat with phosphorus oxychloride and pyridine to form each of the following alkenes?
a.
b.
Textbook Question
What stereoisomers are formed in the following reactions? Which stereoisomer is the major product?
a. the acid-catalyzed dehydration of 1-pentanol to 2-pentene
2
views
Textbook Question
Explain why the following alcohols, when heated with acid, form the same alkene.
2
views
Textbook Question
What stereoisomers are formed in the following reactions? Which stereoisomer is the major product?
b. the acid-catalyzed dehydration of 3,4-dimethyl-3-hexanol to 3,4-dimethyl-3-hexene
Textbook Question
What product is obtained from the reaction of each of the following alcohols with
c. the regents required for a Swern oxidation?
1. 3-pentanol
2. 1-pentanol
3. 2-methyl-2-pentanol