Why is the IR of 4-Methylphenyl 4-bromobenzoate and not 4-bromobenzoic acid? In the IR does it have a presence of both and is there some 4-Dimethylaminopyridine present in the IR? T% 100 Br 90 ob OH 4-bromobenzoic acid 3500 3087 3033 3000 Br 2921 2500 cm-1 1727 olo q N N 4-Methylphenyl 4-bromobenzoate 2000 4-Dimethylaminopyridine

Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
icon
Related questions
icon
Concept explainers
Question
**Infrared Spectroscopy Analysis:**

**Question:**
Why is the IR of 4-Methylphenyl 4-bromobenzoate and not 4-bromobenzoic acid? In the IR, does it have a presence of both, and is there some 4-Dimethylaminopyridine present?

**Infrared Spectrum Analysis:**

The infrared (IR) spectrum presented features a transmittance plot with key peaks identified at specific wavenumbers (cm<sup>-1</sup>).

- **Peak at 3087 cm<sup>-1</sup>:** This peak typically corresponds to aromatic C-H stretching, indicating the presence of aromatic rings.
  
- **Peak at 3033 cm<sup>-1</sup>:** Another characteristic peak for aromatic C-H stretching.
  
- **Peak at 2921 cm<sup>-1</sup>:** Often associated with aliphatic C-H stretching, which may suggest the presence of aliphatic groups.
  
- **Peak at 1727 cm<sup>-1</sup>:** This strong peak is indicative of C=O (carbonyl) stretching, confirming the presence of an ester or carboxylic acid group distinctive of 4-Methylphenyl 4-bromobenzoate.

**Molecular Structures:**

1. **4-bromobenzoic acid:** Features a bromine atom attached to a benzene ring with a carboxylic acid group (-COOH).
   
2. **4-Methylphenyl 4-bromobenzoate:** Includes an ester linkage with a methylphenyl group attached to a benzene ring that has a bromine atom.

3. **4-Dimethylaminopyridine (DMAP):** Contains a pyridine ring with a dimethylamino group.

**Interpretation:**

The spectra displays features more consistent with 4-Methylphenyl 4-bromobenzoate rather than 4-bromobenzoic acid, as evidenced by the ester C=O stretching. There is no clear indication of signals that are characteristic of 4-Dimethylaminopyridine, such as specific N-H or C-N stretches. Thus, it's unlikely that 4-Dimethylaminopyridine is present in significant amounts in this sample based on this IR analysis.

This analysis serves as an example of how IR spectroscopy can be used to identify functional groups and differentiate between similar
Transcribed Image Text:**Infrared Spectroscopy Analysis:** **Question:** Why is the IR of 4-Methylphenyl 4-bromobenzoate and not 4-bromobenzoic acid? In the IR, does it have a presence of both, and is there some 4-Dimethylaminopyridine present? **Infrared Spectrum Analysis:** The infrared (IR) spectrum presented features a transmittance plot with key peaks identified at specific wavenumbers (cm<sup>-1</sup>). - **Peak at 3087 cm<sup>-1</sup>:** This peak typically corresponds to aromatic C-H stretching, indicating the presence of aromatic rings. - **Peak at 3033 cm<sup>-1</sup>:** Another characteristic peak for aromatic C-H stretching. - **Peak at 2921 cm<sup>-1</sup>:** Often associated with aliphatic C-H stretching, which may suggest the presence of aliphatic groups. - **Peak at 1727 cm<sup>-1</sup>:** This strong peak is indicative of C=O (carbonyl) stretching, confirming the presence of an ester or carboxylic acid group distinctive of 4-Methylphenyl 4-bromobenzoate. **Molecular Structures:** 1. **4-bromobenzoic acid:** Features a bromine atom attached to a benzene ring with a carboxylic acid group (-COOH). 2. **4-Methylphenyl 4-bromobenzoate:** Includes an ester linkage with a methylphenyl group attached to a benzene ring that has a bromine atom. 3. **4-Dimethylaminopyridine (DMAP):** Contains a pyridine ring with a dimethylamino group. **Interpretation:** The spectra displays features more consistent with 4-Methylphenyl 4-bromobenzoate rather than 4-bromobenzoic acid, as evidenced by the ester C=O stretching. There is no clear indication of signals that are characteristic of 4-Dimethylaminopyridine, such as specific N-H or C-N stretches. Thus, it's unlikely that 4-Dimethylaminopyridine is present in significant amounts in this sample based on this IR analysis. This analysis serves as an example of how IR spectroscopy can be used to identify functional groups and differentiate between similar
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
IR Spectroscopy of Organic Molecules
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
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY