what exactly is Alkylation? Anyone know.

Alkylation is a reaction in which you add an alkyl group to a molecule. These reactions are unique in the sense that they create a carbon-carbon bond. Not many organic chemistry reactions do this.

So, AlCl3 is a catalyst in this reaction, right?

Yes, AlCl₃ is a catalyst in the Friedel-Crafts acylation.

does an alkylation reaction gives any kind off a minor product

Alkylation can give many products. 1. The alkyl group activates the aromatic ring, so you can get di- and trisubstitution. The ratio of products can vary with temperature. 2. The alkyl cation that is formed as an intermediate can rearrange to form a more stable cation. Thus, the 1-propyl cation (1°) rearranges to the more stable 2° 1-methylethyl (isopropyl) cation. The observed product of the reaction is mostly isopropylbenzene, with only a small amount of propylbenzene.

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Course: Organic chemistry > Unit 9

Lesson 2: Reactions of benzene

Friedel crafts acylation addendum

Name: Friedel crafts acylation addendum
Uploaded: 2014-06-14T15:18:08Z
Description: Friedel-Crafts acylation addendum.

Google Classroom

Friedel-Crafts acylation addendum. Created by Sal Khan.

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salem.chad
Posted 11 years ago. Direct link to salem.chad's post “what exactly is Alkylatio...”
what exactly is Alkylation? Anyone know.
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- Matthew Belliveau
  Posted 11 years ago. Direct link to Matthew Belliveau's post “Alkylation is a reaction ...”
  Alkylation is a reaction in which you add an alkyl group to a molecule. These reactions are unique in the sense that they create a carbon-carbon bond. Not many organic chemistry reactions do this.
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  (19 votes)
kartikagrawal0311
Posted 6 years ago. Direct link to kartikagrawal0311's post “Why Oxygen can't donate a...”
Why Oxygen can't donate a lone pair to aluminium chloride
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rijam thapa
Posted 8 years ago. Direct link to rijam thapa's post “So, AlCl3 is a catalyst i...”
So, AlCl3 is a catalyst in this reaction, right?
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(2 votes)
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- Ernest Zinck
  Posted 8 years ago. Direct link to Ernest Zinck's post “Yes, AlCl₃ is a catalyst ...”
  Yes, AlCl₃ is a catalyst in the Friedel-Crafts acylation.
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mdherrmann
Posted 10 years ago. Direct link to mdherrmann's post “For this reaction, won't ...”
For this reaction, won't the AlCl3 start to bond to the ketone at the end? We were just taught, it was stressed, that you need excess AlCl3, and the complex formed is the product Sal drew, but with the AlCl3 bonded to the Oxygen on the acetophenone (I only know the name because of previous KA videos)... Then, the second step is to add water, which somehow breaks it up and you end up with HO-AlCl3 and a proton in solution. However, I asked for the mechanism, and was not able to get or find it, but could think of at least three ways, but I am uncertain. Does anyone know?
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- marion visser
  Posted 8 years ago. Direct link to marion visser's post “Yes, that's also in my or...”
  Yes, that's also in my organic chemistry book, but indeed not mechanism and nowhere to find one online. They say it is that way, but don't show how. I will just remember this short version then, which is easier to remember than that one with the extra H2O to free this AlCl3 complex :)
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Venkata Sai Ram
Posted 11 years ago. Direct link to Venkata Sai Ram's post “does an alkylation reacti...”
does an alkylation reaction gives any kind off a minor product
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(1 vote)
Answer
- Ernest Zinck
  Posted 11 years ago. Direct link to Ernest Zinck's post “Alkylation can give many ...”
  Alkylation can give many products.
  1. The alkyl group activates the aromatic ring, so you can get di- and trisubstitution. The ratio of products can vary with temperature.
  2. The alkyl cation that is formed as an intermediate can rearrange to form a more stable cation. Thus, the 1-propyl cation (1°) rearranges to the more stable 2° 1-methylethyl (isopropyl) cation. The observed product of the reaction is mostly isopropylbenzene, with only a small amount of propylbenzene.
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  (3 votes)
Rakshan Tej Baggam
Posted 5 years ago. Direct link to Rakshan Tej Baggam's post “at last some aluminium hy...”
at last some aluminium hydroxide will also be formed?why
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Talha Farooq
Posted 8 years ago. Direct link to Talha Farooq's post “on which position electro...”
on which position electrophile attack
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(1 vote)
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cabrams4
Posted 6 years ago. Direct link to cabrams4's post “Does it matter what hydro...”
Does it matter what hydrogen you add the ketone to? Or can this reaction happen on any of them?
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- ggadget6
  Posted 6 years ago. Direct link to ggadget6's post “I'm not sure what you mea...”
  I'm not sure what you mean by what hydrogen - The ketone is not being added to a hydrogen! The ketone is being added to a carbon. The hydrogen is just bonded to that same carbon. However, you are right in that the reaction could happen to any of the carbons on the ring.
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varghesesherwin
Posted 5 years ago. Direct link to varghesesherwin's post “I have a doubt regarding ...”
I have a doubt regarding acylation. when acylbenzene is reacted in presence of cl2/alcl3 ,COCH3 being an electron withdrawing group should place the incoming chlorine on meta position but in the solution it places the incoming chlorine on para position. how's that possible ?
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(1 vote)
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- Ryan W
  Posted 5 years ago. Direct link to Ryan W's post “Note that o/m/p directors...”
  Note that o/m/p directors only tell you what is most likely, in reality all products are formed in different amounts.
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Twishampati Ghosh
Posted 7 years ago. Direct link to Twishampati Ghosh's post “Instead of AlCl3, can we ...”
Instead of AlCl3, can we use FeCl3 for the purpose?? Does it always have to be acetyl chloride or we can use some other reagent for the pupose??
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Video transcript

I want to add one super fast addendum to the video on Friedel-Crafts acylation. In the last step of the mechanism I had this chlorine swipe the electron, or essentially that electron that was with the aluminum. It was given to the hydrogen proton. So the hydrogen was nabbed away. Its electron was allowed to go back into the benzene ring. So the aluminum lost a chlorine. This benzene ring lost a proton. It was able to take back that electron. And I forgot to draw the hydrogen and the chlorine. So then that results in hydrogen chloride. So you have the hydrogen proton bonded-- it took this electron from the aluminum-- and it is bonded to the chlorine. I didn't want to forget that in that last step of the Friedel-Crafts acylation. We also get some hydrogen chloride.