Textbook Question
What is the major product(s) of each of the following reactions?
d.
2
views
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 64b
Bruice 8th EditionCh. 10 - Reactions of Alcohols, Ethers, Epoxides, Amines, and Sulfur-Containing CompoundsProblem 64bChapter 11, Problem 64b
In Section 10.12, we saw that S-adenosylmethionine (SAM) methylates the nitrogen atom of noradrenaline to form adrenaline, a more potent hormone. If SAM methylates an OH group attached to the benzene ring instead, it completely destroys noradrenaline's activity.
b. Which reaction is more apt to occur, methylation on nitrogen or methylation on oxygen?
Verified step by step guidance1
Understand the context: The problem involves the methylation of noradrenaline by S-adenosylmethionine (SAM). Noradrenaline has functional groups that can be methylated, specifically the nitrogen atom and the oxygen atom of the hydroxyl group attached to the benzene ring. The question asks which site is more likely to undergo methylation.
Analyze the reactivity of the nitrogen atom: The nitrogen atom in noradrenaline is part of an amine group. Amines are nucleophilic due to the lone pair of electrons on the nitrogen, making them reactive toward electrophiles like the methyl group from SAM. This nucleophilicity makes the nitrogen a favorable site for methylation.
Analyze the reactivity of the oxygen atom: The oxygen atom in the hydroxyl group attached to the benzene ring is also nucleophilic due to its lone pairs of electrons. However, the hydroxyl group is part of a phenol structure, where the lone pairs on oxygen are partially delocalized into the aromatic ring. This delocalization reduces the nucleophilicity of the oxygen compared to the nitrogen.
Consider steric and electronic factors: Methylation on the nitrogen atom is more likely because the nitrogen is more nucleophilic and less hindered compared to the oxygen atom. Additionally, the methylation of the nitrogen atom leads to the formation of adrenaline, which is biologically significant, suggesting that the enzyme catalyzing this reaction is optimized for nitrogen methylation.
Conclude the comparison: Based on the nucleophilicity and the biological context, methylation on the nitrogen atom is more apt to occur than methylation on the oxygen atom of the hydroxyl group attached to the benzene ring.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Methylation Reactions
Methylation is a biochemical process where a methyl group (CH3) is added to a molecule, often affecting its function. In the context of organic chemistry, methylation can occur on various functional groups, such as nitrogen or oxygen. The reactivity and stability of the resulting compound depend on the nature of the atom being methylated and the surrounding chemical environment.
Recommended video:
Guided course
03:50
Haloform Reaction
Functional Group Reactivity
Different functional groups exhibit varying reactivities due to their electronic and steric properties. Nitrogen atoms, especially in amines, are generally more nucleophilic than oxygen atoms in alcohols or phenols, making them more likely to undergo methylation. Understanding the reactivity of these functional groups is crucial for predicting the outcome of methylation reactions.
Recommended video:
Guided course
02:36Identifying Functional Groups
Biological Significance of Methylation
Methylation plays a vital role in biological systems, influencing the activity of hormones and neurotransmitters. For instance, the methylation of noradrenaline to form adrenaline enhances its potency as a hormone. Conversely, methylation on an oxygen atom can lead to loss of biological activity, highlighting the importance of the specific site of methylation in determining molecular function.
Recommended video:
Guided course
02:08Organic molecules in your everyday life.
Related Practice
Textbook Question
Explain why the acid-catalyzed dehydration of an alcohol is a reversible reaction, whereas the base-promoted dehydrohalogenation of an alkyl halide is an irreversible reaction.
8
views
Textbook Question
What is the major product(s) of each of the following reactions?
h.
1
views
Textbook Question
What is the major product(s) of each of the following reactions?
g.
Textbook Question
An unknown alcohol with a molecular formula of C7H14O was oxidized to an aldehyde with HOCl. When an acidic solution of the alcohol was distilled, two alkenes were obtained. The alkene formed in greater yield was determined to be 1-methylcyclohexene. The other alkene formed the original un-known alcohol when treated with BH3/THF followed by H2O2, HO-, and H2O. Identify the unknown alcohol.
9
views
Textbook Question
Explain why (S)-2-butanol forms a racemic mixture when it is heated in sulfuric acid.