chemist1243
Hazard to Others
Posts: 170
Registered: 7-8-2019
Member Is Offline
|
|
FC alkylation?
ive been trying to find info on how the FC alkylation is carried out in practice, but i can only find mechanisms for the reaction and explanations on
how it works, not actual examples of the reaction.
lets say we have benzene and ethyl chloride, as well as AlCl3 catalyst. how would ethylbenzene be made from these products? what conditions are
necessary for the reaction to take place?
any and all advice and info would be appreciated.
|
|
|
Pumukli
National Hazard
Posts: 708
Registered: 2-3-2014
Location: EU
Member Is Offline
Mood: No Mood
|
|
If your goal is ethylbenzene then forget FC alkylation. It produces a mixture (due to "overalkylation").
You should start from acetophenone and reduce it Wolff-Kishner way. Or something like that.
To have acetophenone you can FC ACYLATE benzene with acetyl-chloride and AlCl3. FC acylations are much better than alkylations because they are
self-limiting: only one acyl group enters the molecule and there are no" over acylations")
(Of course, it is a bit more complicated than this, but for starters it is good enough.)
|
|
|
DraconicAcid
International Hazard
Posts: 4357
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
I have a good prep for t-butylation of biphenyl with FeCl3 as a catalyst. You don't get over-alkylation, because the group is too bulky. Now, can I
find it?
This isn't the one, but the use of aluminum to generate anhydrous AlCl3 in situ is neat:
https://www.ocf.berkeley.edu/~jmlvll/lab-reports/friedelCraf...
[Edited on 17-12-2019 by DraconicAcid]
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
|
|
|
chemist1243
Hazard to Others
Posts: 170
Registered: 7-8-2019
Member Is Offline
|
|
Quote: Originally posted by Pumukli  | If your goal is ethylbenzene then forget FC alkylation. It produces a mixture (due to "overalkylation").
You should start from acetophenone and reduce it Wolff-Kishner way. Or something like that.
To have acetophenone you can FC ACYLATE benzene with acetyl-chloride and AlCl3. FC acylations are much better than alkylations because they are
self-limiting: only one acyl group enters the molecule and there are no" over acylations")
(Of course, it is a bit more complicated than this, but for starters it is good enough.) |
would a FC acylation of benzene with chloroacetone be a good start?
[Edited on 17-12-2019 by chemist1243]
|
|
|
DraconicAcid
International Hazard
Posts: 4357
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
You can't acylate benzene with chloroacetone- it's not an acyl halide. You can use acetyl chloride instead.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
|
|
|
dextro88
Hazard to Self
Posts: 60
Registered: 20-10-2018
Location: In the lab
Member Is Offline
Mood: loading...
|
|
you can do it, buts its low yield reaction, and you gona end up with phenylacetone wich is pretty illegal....
|
|
|
DavidJR
National Hazard
Posts: 908
Registered: 1-1-2018
Location: Scotland
Member Is Offline
Mood: Tired
|
|
| Quote: Originally posted by dextro88 | | you can do it, buts its low yield reaction, and you gona end up with phenylacetone wich is pretty illegal.... |
No, you're missing the point. You can't acylate anything with chloroacetone. You can alkylate benzene with chloroacetone though.
|
|
|
fusso
International Hazard
Posts: 1922
Registered: 23-6-2017
Location: 4 ∥ universes ahead of you
Member Is Offline
|
|
| Quote: Originally posted by DavidJR | | No, you're missing the point. You can't acylate anything with chloroacetone. You can alkylate benzene with
chloroacetone though. |
Fixed the format for ya.
|
|
|
DavidJR
National Hazard
Posts: 908
Registered: 1-1-2018
Location: Scotland
Member Is Offline
Mood: Tired
|
|
It wasn't actually broken...
|
|
|
chemist1243
Hazard to Others
Posts: 170
Registered: 7-8-2019
Member Is Offline
|
|
oooh, so you're saying that if the chlorine on the molecule is not directly bonded to the carbonyl carbon, then the proposed molecule cant participate
in FC ACYLATION, only AKYLATION?
what are some easy to obtain/make acyl chlorides? im starting to get interesting in working with them, particularly by starting with benzene and
working my way up to bigger molecules, so after acylation it shouldnt be terribly difficult to just go from there and make bigger molecules.
|
|
|
DavidJR
National Hazard
Posts: 908
Registered: 1-1-2018
Location: Scotland
Member Is Offline
Mood: Tired
|
|
Acid anhydrides can also be used for FC acylation.
|
|
|
Tsjerk
International Hazard
Posts: 3032
Registered: 20-4-2005
Location: Netherlands
Member Is Offline
Mood: Mood
|
|
| Quote: Originally posted by chemist1243 |
oooh, so you're saying that if the chlorine on the molecule is not directly bonded to the carbonyl carbon, then the proposed molecule cant participate
in FC ACYLATION, only AKYLATION?
what are some easy to obtain/make acyl chlorides? im starting to get interesting in working with them, particularly by starting with benzene and
working my way up to bigger molecules, so after acylation it shouldnt be terribly di
fficult to just go from there and make bigger molecules. |
Edit :have to think twice, will be back
[Edited on 18-12-2019 by Tsjerk]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
