Hi!
I'm very intrestingly, who is tried to make it?
Someone has articles about it? Thanks for the help.
Method of making phenylacetone derivatives
Example 1
75 g. of 15% potassium hydroxide is added to 23.3 g. 1-(3,4-methylenedioxyphenyl)-1,2-dichloropropane and agitated 10 hours, cooled to room
temperature, extracted twice with 200 ml benzene, dried and evaporated (with heat) to get 15.2 g. 3,4-methylenedioxyphenylacetone(yield 85.4 %). The
boiling point is 149-151º C/10mm Hg.
Example 2
80 g. 20 % sodium hydroxide is added to 33.8 g. 1-(3,4-dimethoxyphenyl)-1,2-dibromopropane (melting point 90-93º C.) and boiled for 12 hours. After
steam distillation and extraction with benzene 18.4 g. of a light yellow color oil is obtained. It is pure 3,4-dimethoxyphenylacetone (yield 95.0 %).
The boiling point is 133-137º C/10mm Hg.
[Èçìåíåíî 16-7-2008 ... cannizzaro]
<sub>Edit by Nicodem: Changed the "P2P" acronym from the title.</sub>
[Edited on 17/7/2008 by Nicodem]Filemon - 16-7-2008 at 13:18
..and how do you make the 1-(3,4-methylenedioxyphenyl)-1,2-dichloropropane? It will be [...]2,2-dichoropropanecannizzaro - 16-7-2008 at 13:41
Very simply,
C6H5CHO---C2H5MgBr--->C6H5CH(OH)CH2CH3---KHSO4--
-->C6H5CH=CHCH3---Br2--->C6H5CHBrCHBrCH3---NaOH--->P2P or phenylacetone derivatives, but I cannot find a technique of last transformation,
help me if you knowFilemon - 16-7-2008 at 15:30
It doesn't work this way:
C6H5CHBrCHBrCH3---NaOH---> C6H5CCCH3 => C6H5CCCH3 + H2O + Hg2+ + H+ => C6H5COCHCH3 and C6H5CH2COCH3cannizzaro - 16-7-2008 at 16:36
now I want to found articles about transformation:
C6H5CH=CHCH3---1)H2O2,HCOOH;2)[H+]--->P2P
You'll most likely find more generic or using other alkenes for the diol formation ( http://www.orgsynth.org/orgsyn/pdfs/CV3P0217.pdf ) and the pinacol rearrangement. There is some written on the specific rearrangement, because of
the mechanism for this case.
[Edited on 17-7-2008 by not_important]12AX7 - 16-7-2008 at 21:50
Isomerization? With a methyl?! That's not something they told me about. How does that happen? Inductive effect can't possibly be enough, not with
mere NH2- or OH- around.
Well, actually it goes trough the allene stage (the term diene is more or less used only for two conjugated double bonds) and the isomerization is
driven by the deprotonation trough the enormous difference in pKa's between propargylic C-H and acetylenic C-H (~17 magnitudes of difference).
Regarding the original question of the thread... There is not much else in the literature about Ar-CHX-CHX-Me => Ar-CH2-CO-Me besides the JP patent
already cited (at least nothing that I could find in few minutes of search). Also, all the reaction mechanisms I could imagine don't look something
that would like to happen on such systems. In short, I would be skeptical about that patent until additional information.
Quote:
Originally posted by ScienceSquirrel
Making phenylacetone or its analogues outside an experimental lab is an offence in most places.
Get a job, find yourself a friend, have a nice life, maybe have a few children together.
I can agree with the advice bellow but the your claim about making of phenylacetone "analogues" being a legal offense is simply not true. Preparing
phenylacetone is not a crime in most of the world and neither is preparing its ring substituted versions or whatever analogue (= similar compounds,
which is a term so vague as to mean nothing). However, here I do not like to see any recipe oriented discussions on the synthesis of phenylacetone
itself, most particularly if the original poster uses acronyms like "P2P" or any acronym of criminal background. So, to all those replying, please
stick to the chemistry. If the discussion diverges out of the chemical discourse too much, then you all know where this thread will end.cannizzaro - 16-7-2008 at 23:06
Quote:
Îðèãèíàëüíîå ñîîáùåíèå îò ScienceSquirrel
Making phenylacetone or its analogues outside an experimental lab is an offence in most places.
Get a job, find yourself a friend, have a nice life, maybe have a few children together.
maybe you are right...not_important - 16-7-2008 at 23:34
Quote:
Originally posted by Nicodem
Well, actually it goes trough the allene stage (the term diene is more or less used only for two conjugated double bonds) ...
Yeah, you're right. Never type tech stuff while cooking, the mind is elsewhere.12AX7 - 17-7-2008 at 02:16
Ah, fascinating. So between OH- and NH2-, one could interconvert terminal vs. internal alkyne? Or wait, the water step was uber slow, or is heat
enough to make that move? Oh well, I'm going to bed anyway
TimScienceSquirrel - 17-7-2008 at 05:03
OK, I typed too hastily but some people who are intending to make 3,4-methylenedioxyphenylacetone will be ending up in the local chokey when they
carry out their next step.
[Edited on 17-7-2008 by ScienceSquirrel]not_important - 17-7-2008 at 08:01
Quote:
Originally posted by 12AX7
Ah, fascinating. So between OH- and NH2-, one could interconvert terminal vs. internal alkyne? Or wait, the water step was uber slow, or is heat
enough to make that move?
Yup - takes heating over solid KOH to happen fast enough to be useful. If there several isomeric internal alkynes you usually get a mixture, and side
reactions occur with both OH and amines.
The diamines used in the newer reports work better for getting the terminal alkyne than plain old -NH2; and you need an excess of the amide so as to
lock the terminal alkyne. With KOH and the shift to internal you can use lesser amounts of the base.Filemon - 18-7-2008 at 10:11