Smyrkkeli
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Need help with the Perkin condensation reaction.
I can not seem to find an "easy-to-comprehend" reaction mechanism for the Perkin condensation reaction anywhere on the internet. I conducted a lab
where I reacted benzaldehyde with acetic anhydride to yield trans-cinnamic acid (using potassium acetate as a catalyst) and now I need to come up with
the reaction mechanism.
However, I have not yet had the topic of organic chemistry in school so my understanding of reaction mechanisms is very limited. If someone could
explain it to me, I would be eternally grateful. 
Also, when I did the reflux, an oily and aromatic brown liquid was also made. It formed a liquid bead at the bottom of the solution which seems
hydrophobic. My teacher said that it is probably some polymer. Can anyone verify?
This youtube video that is unrelated to my experiment seems to have a similar, if not the same, side-product forming https://youtu.be/7oAcT4Duun4?t=7m13s.
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madhandevireddy
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Hi,plz tell me how can u identified to completion of reaction?That reaction must proceed 24 hrs after that distilled Ac2o add 10%NAOH Solution then
refulx for 30 Mints then cooled Rt then Add Dil Hcl at pH =2 if solid appeared filtered.Solid is not then extracted with ethyl acetate.then
concentrated and filtered.
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Magpie
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Here's a mechanism. The first eqn is the summary. Ac2O is acetic anhydride. Ar-CHO is the aldehyde, benzaldehyde in this case.
I don't know how to simplify this further.
http://www.sciencemadness.org/talk/files.php?pid=161515&...
You can read of the experiences of others in the thread "cinnamic acid:
http://www.sciencemadness.org/talk/viewthread.php?tid=12746
12746
[Edited on 28-7-2016 by Magpie]
[Edited on 28-7-2016 by Magpie]
The single most important condition for a successful synthesis is good mixing - Nicodem
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