Skip to main content
Ch. 23 - Benzene I: Aromatic Stability and Substitution Reactions
Mullins - Organic Chemistry: A Learner Centered Approach 1st Edition
Mullins1st EditionOrganic Chemistry: A Learner Centered ApproachISBN: 9780137566471Not the one you use?Change textbook
All textbooksMullins 1st EditionCh. 23 - Benzene I: Aromatic Stability and Substitution ReactionsProblem 74c
Chapter 22, Problem 74c

Suggest a synthesis of each of the molecules shown beginning with benzene.
(c)

Verified step by step guidance
1
Start with benzene as the base molecule. The target molecule is 2,4-dichloroacetophenone, which requires the introduction of two chlorine atoms and an acetyl group onto the benzene ring.
Perform a Friedel-Crafts acylation to introduce the acetyl group. Use acetyl chloride (CH3COCl) and aluminum chloride (AlCl3) as the catalyst to add the acetyl group to the benzene ring, forming acetophenone.
Next, perform a chlorination reaction to introduce the chlorine atoms. Use chlorine (Cl2) in the presence of a Lewis acid catalyst like iron(III) chloride (FeCl3) to add chlorine atoms to the ortho and para positions relative to the acetyl group.
Ensure that the reaction conditions favor the formation of the 2,4-dichloroacetophenone by controlling the temperature and the amount of chlorine used to avoid over-chlorination.
Finally, purify the product using techniques such as recrystallization or column chromatography to isolate the desired 2,4-dichloroacetophenone from any side products or unreacted starting materials.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Electrophilic Aromatic Substitution (EAS)

Electrophilic Aromatic Substitution is a fundamental reaction in organic chemistry where an electrophile replaces a hydrogen atom on an aromatic ring, such as benzene. This reaction is crucial for synthesizing various substituted aromatic compounds. The stability of the aromatic system allows for the introduction of different functional groups, which can be further manipulated in subsequent reactions.
Recommended video:
Guided course
03:07
EAS Review

Reactivity of Benzene Derivatives

Benzene derivatives exhibit unique reactivity patterns due to the presence of substituents that can either activate or deactivate the ring towards electrophilic attack. For instance, electron-donating groups enhance reactivity, while electron-withdrawing groups decrease it. Understanding these effects is essential for predicting the outcomes of synthetic routes starting from benzene.
Recommended video:
Guided course
02:49
Aromatic synthesis starting with benzene/benzene derivatives

Functional Group Transformations

Functional group transformations involve converting one functional group into another through various chemical reactions. In the context of synthesizing the given molecule from benzene, transformations such as oxidation, halogenation, and substitution are key. Recognizing how to manipulate these functional groups allows chemists to design effective synthetic pathways to achieve desired products.
Recommended video:
Guided course
02:36
Identifying Functional Groups
Related Practice
Textbook Question

Molecule A is significantly more water soluble than molecule B. Justify this observation.

1
views
Textbook Question

Predict the major product(s) that would result when molecules (a)–(i) are allowed to react under the following conditions. (iv) chlorocyclopentane, AlCl3, (v) 1-chloro-1-methylcyclohexane , AlCl3, (vi) PhCOCl, AlCl3. If no reaction will occur, indicate by writing NR.

(a)

2
views
Textbook Question

Protonation of aniline slows electrophilic aromatic substitution and directs electrophiles to the meta position. Why?

1
views
Textbook Question

Indigo is a dye that was originally isolated from coal tar. In 1905, Johann Friedrich Wilhelm Adolf von Baeyer won a Nobel Prize for a method that allowed indigo to be isolated from plants [a green chemist ahead of his time.] If you nitrated indigo using the reaction learned in this chapter, at which carbon would you expect the nitro group to attach?

1
views
Textbook Question

In Section 17.7.4, we studied the acid-catalyzed hydrolysis of acetals. The acetal shown here resists hydrolysis by the mechanism in Figure 17.63. Why? [Draw the intermediates as if the reaction would occur, then analyze the intermediates for any problems.]

1
views
Textbook Question

Bromination of phenol or aniline does not require the use of a Lewis acid catalyst and often results in trihalogenation. Why?

1
views