Logout Open In App
Open In App
Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

Chapter 4: Problem 51

An ester is a derivative of a carboxylic acid in which the hydrogen of the carboxyl group is replaced by an alkyl group (Section 1.3E). Draw a structural formula of methyl acetate, which is derived from acetic acid by replacement of the \(\mathrm{H}\) of its - \(\mathrm{OH}\) group by a methyl group. Determine whether proton transfer to this compound from \(\mathrm{HCl}\) occurs preferentially on the oxygen of the \(\mathrm{C}=\mathrm{O}\) group or on the oxygen of the \(\mathrm{OCH}_{3}\) group.

Short Answer

Expert verified
Answer: The oxygen atom in the C=O group prefers to accept a proton from HCl.

Step by step solution

01

Draw the structural formula of acetic acid.

The acetic acid has the chemical formula \(\mathrm{CH}_{3}\mathrm{COOH}\). The structural formula for acetic acid is: H H H O \ / \ / C - C = O | | OH The acetic acid consists of a carboxylic acid group (COOH) and a methyl group (CH3).
02

Replace the H of the OH group with a methyl group.

To form methyl acetate, we replace the hydrogen (H) of the -OH group in acetic acid with a methyl group (CH3). The structural formula for methyl acetate, also known as ethanoate, is: H H H O O H \ / \ || / C - C - C | | | H H
03

Analyze proton transfer from HCl to methyl acetate.

We have two possible sites for proton transfer in methyl acetate: 1. The oxygen of the \(\mathrm{C}=\mathrm{O}\) group (carbonyl oxygen) 2. The oxygen of the \(\mathrm{OCH}_{3}\) group (alkoxy oxygen)
04

Determine which oxygen atom is more likely to accept the proton.

The carbonyl oxygen (C=O) is more electronegative and has a stronger electron withdrawing effect than the alkoxy oxygen (OCH3). Therefore, the carbonyl oxygen is more likely to accept the proton (from HCl) because it possesses a higher electron density, making it a better site for protonation. In conclusion, the proton transfer to methyl acetate from \(\mathrm{HCl}\) occurs preferentially on the oxygen of the \(\mathrm{C}=\mathrm{O}\) group.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

2,4-Pentanedione is a considerably stronger acid than is acetone (Chapter 19). Write a structural formula for the conjugate base of each acid and account for the greater stability of the conjugate base from 2,4-pentanedione.

Alcohols (Chapter 10) are weak organic acids, \(\mathrm{p} K_{\mathrm{a}} 15-18\). The \(\mathrm{p} K_{\mathrm{a}}\) of ethanol, \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}\), is \(15.9\). Write equations for the equilibrium reactions of ethanol with each base. Which equilibria lie considerably toward the right? Which lie considerably toward the left? (a) \(\mathrm{NaHCO}_{3}\) (b) \(\mathrm{NaOH}\) (c) \(\mathrm{NaNH}_{2}\) (d) \(\mathrm{NH}_{3}\)

Methyl isocyanate, \(\mathrm{CH}_{3}-\mathrm{N}=\mathrm{C}=\mathrm{O}\), is used in the industrial synthesis of a type of pesticide and herbicide known as a carbamate. As a historical note, an industrial accident in Bhopal, India, in 1984 resulted in leakage of an unknown quantity of this chemical into the air. An estimated 200,000 people were exposed to its vapors, and over 2000 of these people died. (a) Write a Lewis structure for methyl isocyanate and predict its bond angles. What is the hybridization of its carbonyl carbon? Of its nitrogen atom? (b) Methyl isocyanate reacts with strong acids, such as sulfuric acid, to form a cation. Will this molecule undergo protonation more readily on its oxygen or nitrogen atom? In considering contributing structures to each hybrid, do not consider structures in which more than one atom has an incomplete octet.

For each pair of molecules or ions, select the stronger base and write its Lewis structure. (a) \(\mathrm{CH}_{3} \mathrm{~S}^{-}\)or \(\mathrm{CH}_{3} \mathrm{O}^{-}\) (b) \(\mathrm{CH}_{3} \mathrm{NH}^{-}\)or \(\mathrm{CH}_{3} \mathrm{O}^{-}\) (c) \(\mathrm{CH}_{3} \mathrm{COO}^{-}\)or \(\mathrm{OH}^{-}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{O}^{-}\)or \(\mathrm{H}^{-}\) (e) \(\mathrm{NH}_{3}\) or \(\mathrm{OH}^{-}\) (f) \(\mathrm{NH}_{3}\) or \(\mathrm{H}_{2} \mathrm{O}\) (g) \(\mathrm{CH}_{3} \mathrm{COO}^{-}\)or \(\mathrm{HCO}_{3}^{-}\) (h) \(\mathrm{HSO}_{4}^{-}\)or \(\mathrm{OH}^{-}\) (i) \(\mathrm{OH}^{-}\)or \(\mathrm{Br}^{-}\)

What is the strongest base that can exist in liquid ammonia as a solvent?
See all solutions

Recommended explanations on Chemistry Textbooks

Inorganic Chemistry

Read Explanation

Organic Chemistry

Read Explanation

Nuclear Chemistry

Read Explanation

Chemical Reactions

Read Explanation

Chemical Analysis

Read Explanation

Chemistry Branches

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free