Give the products, if any, of each of the following reactions: c. benzoic acid + CH 3 CH 2 Cl + AlCl 3 d. benzene + 2 CH 3 Cl + AlCl 3

All right. Hi, everyone. So, first question, let's go ahead and draw the substitution products of the reactions below. Part one is N N dimethyl alene plus two chloral propane plus A L C +03. Part two is phenyl acetate plus methyl chloride plus A L C L three. Now, for both reactions, right? What I'd like to bring to your attention is the fact that we're reacting with an alco hali, we have an and an aromatic compound and we're combining it with a catalyst ACL three. Now, this combination of reagents, if you recall is characteristic of Friedel Craft's cul in which we're going to add the group of our starting ha light to the aromatic ring itself. So let's go ahead and draw out our given O products, right? And let's go ahead and begin with N N dimethyl ale, which I've drawn on the screen already on the left side. So here N N dimethyl ale is of course an AM right? And we call that amines are pretty problematic when it comes to Frito Crafts al collation. And the reason for that is because the nitrogen of your, I mean, actually reacts independently with your catalyst A L C L three because instead of the pi system of the aromatic ring attacking your catalyst, it's the lone pair of electrons or nitrogen that attacks the aluminum of A L C L three. And so that creates a complex that creates a complex which actually blocks any further reaction. It reacts, it blocks any further reaction. Excuse me, because notice how nitrogen now has a positive charge on it, right. That makes it incredibly electron withdrawing, right? It's going to take electron density away from the aromatic ring and bring it towards itself, which drastically decreases the reactivity of the ring and therefore prevents this reaction from occurring at all. So for part one, no reaction actually occurs. So here there's no reaction, right? But let's see if the same is true for our second reaction here involving phenyl acetate. Now, the oxygen of our here is the one that's directly attached to the phenyl group of our phenyl acetate, right. So this is actually what we refer to as an electron donating group, right? Because unlike our positively charged nitrogen, our oxygen here is actually going to donate electrons to the ring via resonance. And so that activates the ring because it makes it more reactive. And recall also that electron donating groups are referred to as Ortho para directors. Why? Because they direct new substitutes towards the Ortho and the positions. So when we react our phenyl acetate with methyl chloride, we're going to end up with two different products, right? Because our methyl group can add to the Ortho or the paras positions. So here we end up with a mixture of products. First one is our Ortho substituted and the second one is our para substituted. Mhm So this right here is going to be your final answer, right? For part one, no reaction occurs at all because the amine itself reacts with your A L C L three and blocks any further reaction. But in your second part, right, your is actually an excellent electron donating group, which therefore directs the methyl group of methyl chloride towards either the Ortho or the paras position leaving you with a mixture of products. And so with that being said, thank you very much for watching and I hope you found this helpful.

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1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
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4. Alkanes and Cycloalkanes4h 17m
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33. The Organic Chemistry of Metabolic Pathways2h 52m
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35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

19. Reactions of Aromatics: EAS and Beyond

Electron Withdrawing Groups

Organic Chemistry

19. Reactions of Aromatics: EAS and Beyond

Electron Withdrawing Groups

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6:52 minutes

Problem 21c,d

Textbook Question

Give the products, if any, of each of the following reactions:
c. benzoic acid + CH₃CH₂Cl + AlCl₃
d. benzene + 2 CH₃Cl + AlCl₃

Verified step by step guidance

Step 1: Recognize the type of reaction. Both reactions involve a benzene ring and a reagent with an alkyl halide (R-Cl) in the presence of AlCl3, which is a Lewis acid catalyst. This suggests that these are Friedel-Crafts reactions, specifically alkylation reactions.

Step 2: For reaction (c), benzoic acid + CH3CH2Cl + AlCl3: Understand that the carboxylic acid group (-COOH) on benzoic acid is an electron-withdrawing group. This deactivates the benzene ring and makes it less reactive toward electrophilic aromatic substitution reactions like Friedel-Crafts alkylation. Therefore, no reaction occurs in this case.

Step 3: For reaction (d), benzene + 2 CH3Cl + AlCl3: The first step involves the generation of the electrophile. AlCl3 reacts with CH3Cl to form a methyl carbocation (CH3⁺), which is the electrophile in this reaction. This is represented as: CH3Cl + AlCl3 → CH3⁺ + AlCl4⁻.

Step 4: The methyl carbocation (CH3⁺) reacts with the benzene ring in an electrophilic aromatic substitution reaction. The benzene ring donates a pair of π-electrons to the CH3⁺, forming a sigma complex (arenium ion). This intermediate then loses a proton (H⁺) to regenerate the aromaticity of the benzene ring, resulting in toluene (methylbenzene).

Step 5: The second CH3Cl molecule can undergo the same process, leading to the formation of a second methyl group on the benzene ring. The position of the second methyl group will depend on the directing effects of the first methyl group. Since the methyl group is an electron-donating group, it is an ortho/para director. Therefore, the final product will be a mixture of ortho-xylene and para-xylene.

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Key Concepts

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

Friedel-Crafts Alkylation

Friedel-Crafts alkylation is a reaction that introduces alkyl groups into an aromatic ring using an alkyl halide and a Lewis acid catalyst, such as AlCl3. The Lewis acid activates the alkyl halide, generating a more reactive carbocation that can then attack the aromatic system. This reaction is crucial for synthesizing substituted aromatic compounds.

Electrophilic Aromatic Substitution

Electrophilic aromatic substitution (EAS) is a fundamental reaction mechanism in organic chemistry where an electrophile replaces a hydrogen atom on an aromatic ring. The aromatic system donates electrons to the electrophile, forming a sigma complex, which then loses a proton to restore aromaticity. Understanding EAS is essential for predicting the outcomes of reactions involving aromatic compounds.

Reactivity of Alkyl Halides

The reactivity of alkyl halides in electrophilic aromatic substitution depends on the structure of the alkyl group and the leaving group. Primary alkyl halides tend to react via a carbocation mechanism, while tertiary halides can stabilize carbocations more effectively. This concept is important for determining the products of reactions involving alkyl halides and aromatic compounds.

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