Textbook Question
Explain why hydroxide ion catalyzes the reaction of piperidine with 2,4-dinitroanisole but has no effect on the reaction of piperidine with 1-chloro-2,4-dinitrobenzene.
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Ch. 18 - Reactions of Benzene and Substituted Benzenes
Bruice8th EditionOrganic ChemistryISBN: 9780135213711
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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
Chapter 19, Problem 101c
Tyramine is an alkaloid found in mistletoe and ripe cheese. Dopamine is a neurotransmitter involved in the regulation of the central nervous system.
c. Give two ways to prepare b-phenylethylamine from b-phenylethyl chloride.
Verified step by step guidance1
Step 1: Understand the structure of β-phenylethylamine and β-phenylethyl chloride. β-phenylethylamine has the structure C6H5-CH2-CH2-NH2, while β-phenylethyl chloride has the structure C6H5-CH2-CH2-Cl. The goal is to replace the chlorine atom in β-phenylethyl chloride with an amine group (-NH2).
Step 2: Method 1 - Use nucleophilic substitution (SN2 reaction). Treat β-phenylethyl chloride with an excess of ammonia (NH3) in a polar aprotic solvent like ethanol. The chlorine atom acts as a leaving group, and ammonia acts as a nucleophile, replacing the chlorine with an amine group. The reaction proceeds as: C6H5-CH2-CH2-Cl + NH3 → C6H5-CH2-CH2-NH2 + HCl.
Step 3: Method 2 - Use Gabriel synthesis. React β-phenylethyl chloride with potassium phthalimide to form a phthalimide derivative. Then, hydrolyze the phthalimide derivative using hydrazine (NH2-NH2) to release the primary amine group. This method avoids over-alkylation and provides a clean conversion to β-phenylethylamine.
Step 4: Ensure reaction conditions are optimized. For SN2 reactions, use a polar aprotic solvent and maintain a low temperature to favor substitution over elimination. For Gabriel synthesis, ensure complete hydrolysis of the phthalimide derivative to release the amine group.
Step 5: Verify the product. Use spectroscopic techniques like NMR or IR to confirm the presence of the amine group (-NH2) and the absence of the chlorine atom in the final product. This ensures the successful conversion of β-phenylethyl chloride to β-phenylethylamine.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Alkaloids
Alkaloids are a class of naturally occurring organic compounds that mostly contain basic nitrogen atoms. They are often derived from plant sources and have significant pharmacological effects on humans and animals. Tyramine, mentioned in the question, is an alkaloid that can influence neurotransmitter release and is found in various foods, particularly aged cheeses.
Nucleophilic Substitution Reactions
Nucleophilic substitution reactions are fundamental organic reactions where a nucleophile attacks an electrophilic carbon atom, replacing a leaving group. In the context of preparing β-phenylethylamine from β-phenylethyl chloride, understanding this mechanism is crucial, as it involves the substitution of the chloride ion with an amine group, typically using a nucleophile like ammonia or an amine.
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01:47
Nucleophiles and Electrophiles can react in Substitution Reactions.
Amines and Their Reactivity
Amines are organic compounds derived from ammonia by replacing one or more hydrogen atoms with alkyl or aryl groups. They are characterized by their basicity and nucleophilicity, making them reactive towards electrophiles. In the synthesis of β-phenylethylamine, the reactivity of amines plays a key role, as they can act as nucleophiles in substitution reactions, facilitating the conversion from halides to amines.
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07:12Reductive Amination
Related Practice
Textbook Question
Tyramine is an alkaloid found in mistletoe and ripe cheese. Dopamine is a neurotransmitter involved in the regulation of the central nervous system.
a. How can tyramine be prepared from b-phenylethylamine?
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Textbook Question
Ibuprofen is the active ingredient in pain relievers such as Advil, Motrin, and Nuprin. How can ibuprofen be synthesized from benzene?
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