Organic Chemistry
Organic Chemistry
9th Edition
ISBN: 9781305080485
Author: John E. McMurry
Publisher: Cengage Learning
bartleby

Concept explainers

bartleby

Videos

Textbook Question
Book Icon
Chapter 20.SE, Problem 25MP

Acid-catalyzed hydrolysis of a nitrile to give a carboxylic acid occurs by initial protonation of the nitrogen atom, followed by nucleophilic addition of water. Review the mechanism of base-catalyzed nitrile hydrolysis in Section 20-7 and then predict the products for each reaction below and write all of the steps involved in the acid-catalyzed reaction, using curved arrows to represent electron flow in each step.

Chapter 20.SE, Problem 25MP, Acid-catalyzed hydrolysis of a nitrile to give a carboxylic acid occurs by initial protonation of

Expert Solution
Check Mark
Interpretation Introduction

a)

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  1

Interpretation:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step, is to be given.

Concept introduction:

The acid protonates the nitrogen of the nitrile group initially. The nucleophilic attack by water and subsequent proton transfer will yield an intermediate. Another nucleophilic attack by water on the intermediate and yet another proton transfer produces another intermediate. The intermediate loses ammonia to produce the protonated acid which deprotonates to yield the acid.

To give:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step.

Answer to Problem 25MP

The products of the reaction are ammonia and 2,2-dimethylbutanoic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  2

Explanation of Solution

In the first step, 2,2-dimethylbutane nitrile is protonated by HCl. In the next step, the nucleophilic attack of water on the protonated nitrile occurs and the accompanying proton transfer yields a protonated aminoketone. Another nucleophilic attack on the carbonyl carbon of the protonated aminoketone in the next step and the subsequent proton transfer yields a protonated diol intermediate which eliminates ammonia and a proton in the subsequent steps to yield 2,2-dimethylbutanoic acid.

Conclusion

The products of the reaction are ammonia and 2,2-dimethylbutanoic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  3

Expert Solution
Check Mark
Interpretation Introduction

b)

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  4

Interpretation:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step, is to be given.

Concept introduction:

The acid protonates the nitrogen of the nitrile group initially. The nucleophilic attack by water and subsequent proton transfer will yield an intermediate. Another nucleophilic attack by water on the intermediate and yet another proton transfer produces another intermediate. The intermediate loses ammonia to produce the protonated acid which deprotonates to yield the acid.

To give:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step.

Answer to Problem 25MP

The products of the reaction are ammonia and p-methylbenzoic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  5

Explanation of Solution

In the first step, p-methylbenzonitrile is protonated by HCl. In the next step, the nucleophilic attack of water on the protonated nitrile occurs and the accompanying proton transfer yields a protonated aminoketone. Another nucleophilic attack on the carbonyl carbon of the protonated aminoketone in the next step and the subsequent proton transfer yields a protonated diol intermediate which eliminates ammonia and a proton in the subsequent steps to yield p-methylbenzoic acid.

Conclusion

The products of the reaction are ammonia and p-methylbenzoic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  6

Expert Solution
Check Mark
Interpretation Introduction

c)

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  7

Interpretation:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step, is to be given.

Concept introduction:

The acid protonates the nitrogen of the nitrile group initially. The nucleophilic attack by water and subsequent proton transfer will yield an intermediate. Another nucleophilic attack by water on the intermediate and yet another proton transfer produces another intermediate. The intermediate loses ammonia to produce the protonated acid which deprotonates to yield the acid.

To give:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step.

Answer to Problem 25MP

The products of the reaction are ammonia and 2-methylbutanoic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  8

Explanation of Solution

In the first step, 2-methylbutane nitrile is protonated by HCl. In the next step, the nucleophilic attack of water on the protonated nitrile occurs and the accompanying proton transfer yields a protonated aminoketone. Another nucleophilic attack on the carbonyl carbon of the protonated aminoketone in the next step and the subsequent proton transfer yields a protonated diol intermediate which eliminates ammonia and a proton in the subsequent steps to yield 2-methylbutanoic acid.

Conclusion

The products of the reaction are ammonia and 2-methylbutanoic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  9

Expert Solution
Check Mark
Interpretation Introduction

d)

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  10

Interpretation:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step, is to be given.

Concept introduction:

The acid protonates the nitrogen of the nitrile group initially. The nucleophilic attack by water and subsequent proton transfer will yield an intermediate. Another nucleophilic attack by water on the intermediate and yet another proton transfer produces another intermediate. The intermediate loses ammonia to produce the protonated acid which deprotonates to yield the acid.

To give:

The products of the reaction, the acid-catalyzed nitrile hydrolysis, along with all the steps involved using curved arrows to represent electron flow in each step.

Answer to Problem 25MP

The products of the reaction are ammonia and cyclopentanecarboxylic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  11

Explanation of Solution

In the first step, cyclopentanenitrile is protonated by HCl. In the next step, the nucleophilic attack of water on the protonated nitrile occurs and the accompanying proton transfer yields a protonated aminoketone. Another nucleophilic attack on the carbonyl carbon of the protonated ketone in the next step and the subsequent proton transfer yields a protonated aminodiol intermediate which eliminates ammonia and a proton in the subsequent steps to yield cyclopentanecarboxylic acid.

Conclusion

The products of the reaction are ammonia and cyclopentanecarboxylic acid.

The mechanism of the reaction is given below.

Organic Chemistry, Chapter 20.SE, Problem 25MP , additional homework tip  12

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Please correct answer and don't used hand raiting
Order-disorder phenomenaa) do not have conductive properties.b) are cooperative.c) have few industrial implications.
None

Chapter 20 Solutions

Organic Chemistry

Ch. 20.6 - Prob. 11PCh. 20.6 - How might you carry out the following...Ch. 20.7 - Prob. 13PCh. 20.7 - Prob. 14PCh. 20.8 - Cyclopentanecarboxylic acid and...Ch. 20.8 - Prob. 16PCh. 20.SE - Prob. 17VCCh. 20.SE - Prob. 18VCCh. 20.SE - The following carboxylic acid can’t be prepared...Ch. 20.SE - Electrostatic potential maps of anisole and...Ch. 20.SE - Predict the product(s) and provide the mechanism...Ch. 20.SE - Predict the product(s) and provide the mechanism...Ch. 20.SE - Prob. 23MPCh. 20.SE - Predict the product(s) and provide the complete...Ch. 20.SE - Acid-catalyzed hydrolysis of a nitrile to give a...Ch. 20.SE - Prob. 26MPCh. 20.SE - Naturally occurring compounds called cyanogenic...Ch. 20.SE - 2-Bromo-6, 6-dimethylcyclohexanone gives 2,...Ch. 20.SE - Naturally occurring compounds called terpenoids,...Ch. 20.SE - In the Ritter reaction, an alkene reacts with a...Ch. 20.SE - Give IUPAC names for the following compounds:Ch. 20.SE - Prob. 32APCh. 20.SE - Prob. 33APCh. 20.SE - Prob. 34APCh. 20.SE - Prob. 35APCh. 20.SE - Prob. 36APCh. 20.SE - Prob. 37APCh. 20.SE - Prob. 38APCh. 20.SE - Calculate the Ka's for the following acids: (a)...Ch. 20.SE - Thioglycolic acid, HSCH2CO2H, a substance used in...Ch. 20.SE - Prob. 41APCh. 20.SE - Prob. 42APCh. 20.SE - How could you convert butanoic acid into the...Ch. 20.SE - How could you convert each of the following...Ch. 20.SE - How could you convert butanenitrile into the...Ch. 20.SE - How would you prepare the following compounds from...Ch. 20.SE - Prob. 47APCh. 20.SE - Using 13CO2 as your only source of labeled carbon,...Ch. 20.SE - Prob. 49APCh. 20.SE - Which method-Grignard carboxylation or nitrile...Ch. 20.SE - Prob. 51APCh. 20.SE - Prob. 52APCh. 20.SE - Propose a structure for a compound C6H12O2 that...Ch. 20.SE - Prob. 54APCh. 20.SE - How would you use NMR (either 13C or 1H) to...Ch. 20.SE - Prob. 56APCh. 20.SE - A chemist in need of 2,2-dimethylpentanoic acid...Ch. 20.SE - Prob. 58APCh. 20.SE - Prob. 59APCh. 20.SE - Prob. 60APCh. 20.SE - Prob. 61APCh. 20.SE - Prob. 62APCh. 20.SE - Prob. 63APCh. 20.SE - The following pKa values have been measured....Ch. 20.SE - Identify the missing reagents a-f in the following...Ch. 20.SE - Propose a structure for a compound, C4H7N, that...Ch. 20.SE - Prob. 67APCh. 20.SE - The 1H and 13C NMR spectra below belong to a...Ch. 20.SE - Propose structures for carboxylic acids that show...Ch. 20.SE - Carboxylic acids having a second carbonyl group...
Knowledge Booster
Background pattern image
Chemistry
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
  • Text book image
    Organic Chemistry
    Chemistry
    ISBN:9781305080485
    Author:John E. McMurry
    Publisher:Cengage Learning
    Text book image
    Organic Chemistry
    Chemistry
    ISBN:9781305580350
    Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
    Publisher:Cengage Learning
    Text book image
    Introduction to General, Organic and Biochemistry
    Chemistry
    ISBN:9781285869759
    Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres
    Publisher:Cengage Learning
Text book image
Organic Chemistry
Chemistry
ISBN:9781305080485
Author:John E. McMurry
Publisher:Cengage Learning
Text book image
Organic Chemistry
Chemistry
ISBN:9781305580350
Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
Publisher:Cengage Learning
Text book image
Introduction to General, Organic and Biochemistry
Chemistry
ISBN:9781285869759
Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar Torres
Publisher:Cengage Learning
Alcohols, Ethers, and Epoxides: Crash Course Organic Chemistry #24; Author: Crash Course;https://www.youtube.com/watch?v=j04zMFwDeDU;License: Standard YouTube License, CC-BY