Organic Chemistry
Organic Chemistry
8th Edition
ISBN: 9781337516402
Author: Brown
Publisher: Cengage
bartleby

Concept explainers

bartleby

Videos

Textbook Question
Book Icon
Chapter 18, Problem 18.18P

Propose a structural formula for each compound consistent with its 1H-NMR and 13C-NMR spectra.

  1. (a) C5H10O2

Chapter 18, Problem 18.18P, Propose a structural formula for each compound consistent with its 1H-NMR and 13C-NMR spectra. (a) , example  1

  1. (b) C7H14O2

Chapter 18, Problem 18.18P, Propose a structural formula for each compound consistent with its 1H-NMR and 13C-NMR spectra. (a) , example  2

  1. (c) C6 H12O2

Chapter 18, Problem 18.18P, Propose a structural formula for each compound consistent with its 1H-NMR and 13C-NMR spectra. (a) , example  3

  1. (d) C7H12O4

Chapter 18, Problem 18.18P, Propose a structural formula for each compound consistent with its 1H-NMR and 13C-NMR spectra. (a) , example  4

  1. (e) C4H7ClO2

Chapter 18, Problem 18.18P, Propose a structural formula for each compound consistent with its 1H-NMR and 13C-NMR spectra. (a) , example  5

  1. (f) C4H6O2

Chapter 18, Problem 18.18P, Propose a structural formula for each compound consistent with its 1H-NMR and 13C-NMR spectra. (a) , example  6

(a)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The structural formula for compound having molecular formula C5H10O2 has to be identified using the given spectral data.

Concept Introduction:

1H NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of hydrogen atoms and the hydrogen atoms.

Chemical shift: The frequency of the proton signal in the spectrum with reference to the standard compound  which may be TMS(Tetramethylsilane) shows signal at 0 ppm(parts per million).

Integration value (I): The integration value at the bottom of the 1HNMR spectrum represents the number of protons giving rise to the signal.

Chemical shift values for protons in different electronic environment

Types of protonsChemical shiftMethyl~0.85Methylene~1.2Methine~1.55Allylic~2Alkynyl~2.5ROCH3~3.3BrCH2H~2.54ClCH2H~34Vinyl~4.56.5Aryl~6.58Aldehyde~10carboxylic~12

FUNCTIONAL GROUPEFFECT ON THE ALPHA PROTONSEFFECT ON THE BETA PROTONS
Oxygen of an alcohol or ether+2.5+0.5
Oxygen of ester+3.0+0.6
Carbonyl groups+1.0+0.2

13C NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of the carbon atoms.

The signals in the 13C NMR spectrum of a compound is proportional to the number of carbons that are present in the different environment within the molecule. The carbon that is present in the electron-rich environment shows a signal at a lower frequency and vice-versa. Therefore, the carbon that is present nearest to the electron-withdrawing groups produces a high-frequency signal.

Explanation of Solution

Given compound has the molecular formula C5H10O2.

Spectral data is given below:

  1H-NMR13C-NMR0.96(d,6H)161.111.96(m,1H)70.013.95(d,2H)27.718.08(s,1H)19.00

By analyzing the spectral data, the structure can be predicted.

The value of 8.08 suggests an aldehyde proton. 0.96 will indicate the presence of methyl groups and 1.96 indicates the methylene proton β to carbonyl group.3.95 suggest the presence of methylene proton α

The structure proposed according to the data is given below:

Organic Chemistry, Chapter 18, Problem 18.18P , additional homework tip  1

(b)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The structural formula for compound having molecular formula C7H14O2 has to be identified using the given spectral data.

Concept Introduction:

1H NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of hydrogen atoms and the hydrogen atoms.

Chemical shift: The frequency of the proton signal in the spectrum with reference to the standard compound  which may be TMS(Tetramethylsilane) shows signal at 0 ppm(parts per million).

Integration value (I): The integration value at the bottom of the 1HNMR spectrum represents the number of protons giving rise to the signal.

Chemical shift values for protons in different electronic environment

Types of protonsChemical shiftMethyl~0.85Methylene~1.2Methine~1.55Allylic~2Alkynyl~2.5ROCH3~3.3BrCH2H~2.54ClCH2H~34Vinyl~4.56.5Aryl~6.58Aldehyde~10carboxylic~12

FUNCTIONAL GROUPEFFECT ON THE ALPHA PROTONSEFFECT ON THE BETA PROTONS
Oxygen of an alcohol or ether+2.5+0.5
Oxygen of ester+3.0+0.6
Carbonyl groups+1.0+0.2

13C NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of the carbon atoms.

The signals in the 13C NMR spectrum of a compound is proportional to the number of carbons that are present in the different environment within the molecule. The carbon that is present in the electron-rich environment shows a signal at a lower frequency and vice-versa. Therefore, the carbon that is present nearest to the electron-withdrawing groups produces a high-frequency signal.

Explanation of Solution

Given compound has the molecular formula C7H14O2.

Spectral data is given below:

  1H-NMR13C-NMR0.92(d,6H)171.151.52(m,6H)63.121.70(m,1H)37.312.09(s,3H)25.054.10(t,2H)22.4521.06

By analyzing the spectral data, the structure can be predicted.

The value of 2.09 indicates a methyl group α to carbonyl group. 4.09 indicate the presence of methylene group directly attached to oxygen of ether and 1.70 suggests the presence of methane group.1.52 indicates the presence of methylene group β to ether.

The structure proposed according to the data is given below:

Organic Chemistry, Chapter 18, Problem 18.18P , additional homework tip  2

(c)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The structural formula for compound having molecular formula C6H12O2 has to be identified using the given spectral data.

Concept Introduction:

1H NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of hydrogen atoms and the hydrogen atoms.

Chemical shift: The frequency of the proton signal in the spectrum with reference to the standard compound  which may be TMS(Tetramethylsilane) shows signal at 0 ppm(parts per million).

Integration value (I): The integration value at the bottom of the 1HNMR spectrum represents the number of protons giving rise to the signal.

Chemical shift values for protons in different electronic environment

Types of protonsChemical shiftMethyl~0.85Methylene~1.2Methine~1.55Allylic~2Alkynyl~2.5ROCH3~3.3BrCH2H~2.54ClCH2H~34Vinyl~4.56.5Aryl~6.58Aldehyde~10carboxylic~12

FUNCTIONAL GROUPEFFECT ON THE ALPHA PROTONSEFFECT ON THE BETA PROTONS
Oxygen of an alcohol or ether+2.5+0.5
Oxygen of ester+3.0+0.6
Carbonyl groups+1.0+0.2

13C NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of the carbon atoms.

The signals in the 13C NMR spectrum of a compound is proportional to the number of carbons that are present in the different environment within the molecule. The carbon that is present in the electron-rich environment shows a signal at a lower frequency and vice-versa. Therefore, the carbon that is present nearest to the electron-withdrawing groups produces a high-frequency signal.

Explanation of Solution

Given compound has the molecular formula C6H12O2.

Spectral data is given below:

  1H-NMR13C-NMR1.18(d,6H)177.161.26(t,3H)60.172.51(m,1H)34.044.13(q,2H)19.0114.25

By analyzing the spectral data, the structure can be predicted.

1.18 and 1.26 will indicate the presence of methyl groups and 4.13 indicates the methylene proton α to oxygen. 2.51 indicate the presence of methine proton attached to a carbonyl group.

The structure proposed according to the data is given below:

Organic Chemistry, Chapter 18, Problem 18.18P , additional homework tip  3

(d)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The structural formula for compound having molecular formula C7H12O4 has to be identified using the given spectral data.

Concept Introduction:

1H NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of hydrogen atoms and the hydrogen atoms.

Chemical shift: The frequency of the proton signal in the spectrum with reference to the standard compound  which may be TMS(Tetramethylsilane) shows signal at 0 ppm(parts per million).

Integration value (I): The integration value at the bottom of the 1HNMR spectrum represents the number of protons giving rise to the signal.

Chemical shift values for protons in different electronic environment

Types of protonsChemical shiftMethyl~0.85Methylene~1.2Methine~1.55Allylic~2Alkynyl~2.5ROCH3~3.3BrCH2H~2.54ClCH2H~34Vinyl~4.56.5Aryl~6.58Aldehyde~10carboxylic~12

FUNCTIONAL GROUPEFFECT ON THE ALPHA PROTONSEFFECT ON THE BETA PROTONS
Oxygen of an alcohol or ether+2.5+0.5
Oxygen of ester+3.0+0.6
Carbonyl groups+1.0+0.2

13C NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of the carbon atoms.

The signals in the 13C NMR spectrum of a compound is proportional to the number of carbons that are present in the different environment within the molecule. The carbon that is present in the electron-rich environment shows a signal at a lower frequency and vice-versa. Therefore, the carbon that is present nearest to the electron-withdrawing groups produces a high-frequency signal.

Explanation of Solution

Given compound has the molecular formula C7H12O4.

Spectral data is given below:

  1H-NMR13C-NMR1.28(t,6H)166.523.36(s,2H)61.434.21(q,4H)41.6914.07

By analyzing the spectral data, the structure can be predicted.

The value of 3.36 suggests a methylene directly attach to a carbonyl group. 1.28 will indicate the presence of methyl groups and 4.21 indicates the methylene proton β to carbonyl group α to oxygen.

The structure proposed according to the data is given below:

Organic Chemistry, Chapter 18, Problem 18.18P , additional homework tip  4

(e)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The structural formula for compound having molecular formula C4H7ClO2 has to be identified using the given spectral data.

Concept Introduction:

1H NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of hydrogen atoms and the hydrogen atoms.

Chemical shift: The frequency of the proton signal in the spectrum with reference to the standard compound  which may be TMS(Tetramethylsilane) shows signal at 0 ppm(parts per million).

Integration value (I): The integration value at the bottom of the 1HNMR spectrum represents the number of protons giving rise to the signal.

Chemical shift values for protons in different electronic environment

Types of protonsChemical shiftMethyl~0.85Methylene~1.2Methine~1.55Allylic~2Alkynyl~2.5ROCH3~3.3BrCH2H~2.54ClCH2H~34Vinyl~4.56.5Aryl~6.58Aldehyde~10carboxylic~12

FUNCTIONAL GROUPEFFECT ON THE ALPHA PROTONSEFFECT ON THE BETA PROTONS
Oxygen of an alcohol or ether+2.5+0.5
Oxygen of ester+3.0+0.6
Carbonyl groups+1.0+0.2

13C NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of the carbon atoms.

The signals in the 13C NMR spectrum of a compound is proportional to the number of carbons that are present in the different environment within the molecule. The carbon that is present in the electron-rich environment shows a signal at a lower frequency and vice-versa. Therefore, the carbon that is present nearest to the electron-withdrawing groups produces a high-frequency signal.

Explanation of Solution

Given compound has the molecular formula C4H7ClO2.

Spectral data is given below:

  1H-NMR13C-NMR1.68(d,3H)170.513.80(s,3H)52.924.42(q,4H)52.3221.52

By analyzing the spectral data, the structure can be predicted.

The value of 4.42 suggests a proton group directly attach to a chlorine group. 3.80 will indicate the presence of methyl group which is α to oxygen and β to carbonyl group. 1.68represent a methyl group β to chlorine.

The structure proposed according to the data is given below:

Organic Chemistry, Chapter 18, Problem 18.18P , additional homework tip  5

(f)

Expert Solution
Check Mark
Interpretation Introduction

Interpretation:

The structural formula for compound having molecular formula C4H6O2 has to be identified using the given spectral data.

Concept Introduction:

1H NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of hydrogen atoms and the hydrogen atoms.

Chemical shift: The frequency of the proton signal in the spectrum with reference to the standard compound  which may be TMS(Tetramethylsilane) shows signal at 0 ppm(parts per million).

Integration value (I): The integration value at the bottom of the 1HNMR spectrum represents the number of protons giving rise to the signal.

Chemical shift values for protons in different electronic environment

Types of protonsChemical shiftMethyl~0.85Methylene~1.2Methine~1.55Allylic~2Alkynyl~2.5ROCH3~3.3BrCH2H~2.54ClCH2H~34Vinyl~4.56.5Aryl~6.58Aldehyde~10carboxylic~12

FUNCTIONAL GROUPEFFECT ON THE ALPHA PROTONSEFFECT ON THE BETA PROTONS
Oxygen of an alcohol or ether+2.5+0.5
Oxygen of ester+3.0+0.6
Carbonyl groups+1.0+0.2

13C NMR spectroscopy:

It is the study of the interaction between electromagnetic radiation and the nuclei of the carbon atoms.

The signals in the 13C NMR spectrum of a compound is proportional to the number of carbons that are present in the different environment within the molecule. The carbon that is present in the electron-rich environment shows a signal at a lower frequency and vice-versa. Therefore, the carbon that is present nearest to the electron-withdrawing groups produces a high-frequency signal.

Explanation of Solution

Given compound has the molecular formula C5H10O2.

Spectral data is given below:

  1H-NMR13C-NMR2.29(m,2H)177.812.50(t,2H)68.584.36(t,2H)27.7922.17

By analyzing the spectral data, the structure can be predicted.

The value of 4.36 suggests a methylene directly attach to a oxygen group. 2.50 will indicate the presence of methylene proton α to carbonyl and 2.29 indicates methylene proton β to carbonyl group.

The structure proposed according to the data is given below:

Organic Chemistry, Chapter 18, Problem 18.18P , additional homework tip  6

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
Identifying the major species in weak acid or weak base equilibria The preparations of two aqueous solutions are described in the table below. For each solution, write the chemical formulas of the major species present at equilibrium. You can leave out water itself. Write the chemical formulas of the species that will act as acids in the 'acids' row, the formulas of the species that will act as bases in the 'bases' row, and the formulas of the species that will act as neither acids nor bases in the 'other' row. You will find it useful to keep in mind that HF is a weak acid. acids: 0.2 mol of KOH is added to 1.0 L of a 0.5 M HF solution. bases: Х other: ☐ acids: 0.10 mol of HI is added to 1.0 L of a solution that is 1.4M in both HF and NaF. bases: other: ☐ 0,0,... ด ? 18 Ar
Identifying the major species in weak acid or weak base equilibria The preparations of two aqueous solutions are described in the table below. For each solution, write the chemical formulas of the major species present at equilibrium. You can leave out water itself. Write the chemical formulas of the species that will act as acids in the 'acids' row, the formulas of the species that will act as bases in the 'bases' row, and the formulas of the species that will act as neither acids nor bases in the 'other' row. You will find it useful to keep in mind that NH3 is a weak base. acids: ☐ 1.8 mol of HCl is added to 1.0 L of a 1.0M NH3 bases: ☐ solution. other: ☐ 0.18 mol of HNO3 is added to 1.0 L of a solution that is 1.4M in both NH3 and NH₁Br. acids: bases: ☐ other: ☐ 0,0,... ? 000 18 Ar B 1
Using reaction free energy to predict equilibrium composition Consider the following equilibrium: 2NH3 (g) = N2 (g) +3H₂ —N2 (g) AGº = 34. kJ Now suppose a reaction vessel is filled with 4.19 atm of ammonia (NH3) and 9.94 atm of nitrogen (N2) at 378. °C. Answer the following questions about this system: rise Under these conditions, will the pressure of NH 3 tend to rise or fall? ☐ x10 fall Х Is it possible to reverse this tendency by adding H₂? In other words, if you said the pressure of NH 3 will tend to rise, can that be changed to a tendency to fall by adding H₂? Similarly, if you said the pressure of NH3 will tend to fall, can that be changed to a tendency to rise by adding H₂? If you said the tendency can be reversed in the second question, calculate the minimum pressure of H₂ needed to reverse it. Round your answer to 2 significant digits. yes no atm 00. 18 Ar 무ㅎ ?

Chapter 18 Solutions

Organic Chemistry

Ch. 18.8 - The following sequence of steps is used to create...Ch. 18.9 - Prob. 18.8PCh. 18.9 - Prob. 18.9PCh. 18.10 - Prob. 18.10PCh. 18.10 - Show how to convert (R)-2-phenylpropanoic acid to...Ch. 18 - Prob. 18.12PCh. 18 - Write the IUPAC name for each compound. (a)...Ch. 18 - Prob. 18.14PCh. 18 - Prob. 18.15PCh. 18 - Propose a structural formula for compound A,...Ch. 18 - Propose a structural formula for compound B,...Ch. 18 - Propose a structural formula for each compound...Ch. 18 - Draw a structural formula for the principal...Ch. 18 - Prob. 18.20PCh. 18 - Prob. 18.21PCh. 18 - Prob. 18.22PCh. 18 - Prob. 18.23PCh. 18 - Prob. 18.24PCh. 18 - Show the product expected when the following...Ch. 18 - The reagent diisobutylaluminum hydride (DIBALH)...Ch. 18 - Prob. 18.27PCh. 18 - Prob. 18.28PCh. 18 - Prob. 18.29PCh. 18 - Nicotinic acid, more commonly named niacin, is one...Ch. 18 - Prob. 18.31PCh. 18 - Prob. 18.32PCh. 18 - Prob. 18.33PCh. 18 - Prob. 18.34PCh. 18 - Prob. 18.35PCh. 18 - Isoniazid, a drug used to treat tuberculosis, is...Ch. 18 - Prob. 18.37PCh. 18 - A step in a synthesis of PGE1 (prostaglandin E1,...Ch. 18 - Prob. 18.39PCh. 18 - Prob. 18.40PCh. 18 - Show how to synthesize 5-nonanone from...Ch. 18 - Prob. 18.42PCh. 18 - The following sequence of steps converts...Ch. 18 - Prob. 18.44PCh. 18 - Prob. 18.45PCh. 18 - Prob. 18.46PCh. 18 - Prob. 18.47PCh. 18 - Following is a retrosynthetic analysis for the...Ch. 18 - Prob. 18.50PCh. 18 - Given this retrosynthetic analysis, propose a...Ch. 18 - Prob. 18.52PCh. 18 - Prob. 18.53PCh. 18 - Prob. 18.54PCh. 18 - In Problem 7.28, we saw this step in Johnsons...Ch. 18 - Prob. 18.56PCh. 18 - Prob. 18.57PCh. 18 - Prob. 18.58PCh. 18 - Prob. 18.59PCh. 18 - Prob. 18.60PCh. 18 - Prob. 18.61PCh. 18 - Prob. 18.62PCh. 18 - Using your reaction roadmap as a guide, show how...Ch. 18 - Using your reaction roadmap as a guide, show how...Ch. 18 - Using your reaction roadmap as a guide, show how...Ch. 18 - Using your reaction roadmap as a guide, show how...Ch. 18 - Minoxidil is a molecule that causes hair growth in...Ch. 18 - Prob. 18.69PCh. 18 - Prob. 18.70PCh. 18 - Prob. 18.71P
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:9781305580350
    Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote
    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
NMR Spectroscopy; Author: Professor Dave Explains;https://www.youtube.com/watch?v=SBir5wUS3Bo;License: Standard YouTube License, CC-BY