Author Topic: allybenzene to phenylacetone  (Read 808 times)

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psytech

  • Guest
allybenzene to phenylacetone
« on: January 19, 2003, 02:42:00 PM »
Journal of Organic chemistry, vol 45, pages 5390-92 (1980)
Here they describe coverting allybenzenes to p2p's using,
t-butyl alochol,h2o2,and palladium acetate. I've UTFSE I couldn't find anything. Feed back would be nice  :)

hCiLdOdUeDn

  • Guest
wacker oxidiation
« Reply #1 on: January 19, 2003, 05:13:00 PM »
Is there anything significantly better with that method? This is essentially the same as a wacker oxidation using a palladium (salt) catalyst to covert allylbenzene to ketones. All over the FSE and Rhodiums excellent website.


Rhodium

  • Guest
Problems with the H2O2/t-BuOH Wacker
« Reply #2 on: January 19, 2003, 05:50:00 PM »
It has been discussed before (way back actually). For starters, the full text is to be found in

Post 108450 (missing)

(dormouse: "scanboy strikes again... H2O2, Pd(AcO)2  -quirks", Novel Discourse)
.

If you take a look in

Post 108388 (missing)

(dormouse: "PdCl2 --> Pd(Ac)2. Help  -sunlight", Novel Discourse)
and

Post 108468 (missing)

(dormouse: "Dream WoRkS - Oxidation Olefin via Pd Acetate  -SCx", Novel Discourse)
you'll see that people actually had quite some problems with the method, it seems like the main product gotten from plugging Safrole into the above reaction is MDP-3-P (3,4-Methylenedioxyphenylpropanal).

psytech

  • Guest
thanks rhodium
« Reply #3 on: January 19, 2003, 09:10:00 PM »
another method that seems just to easy to be true

Sunlight

  • Guest
If you like research...
« Reply #4 on: January 20, 2003, 07:52:00 AM »
I've tried a few variation of that method with safrol, and using ethyl acetate and Pd(NO3)2 and refluxing conditions seems to give the ketone (TLC) and safrol as the main products. You may try it if you have the time.

yellium

  • Guest
IIRC, there was also somebody who showed that...
« Reply #5 on: January 20, 2003, 09:49:00 AM »
IIRC, there was also somebody who showed that the h2o2 wacker depended critically on the safrole addition speed. Amonst others.

Sunlight

  • Guest
Pd(AcO)2
« Reply #6 on: January 22, 2003, 05:55:00 AM »
There is a easier way to prepare Pd diacetate or other salts, just dissolve the PdCl2 in acid conditions, then neutralize wtih cooling around 60 C to precipite Pd hydroxides and filter, wash and treat with your acid. I've seen it in some patents posted by PolyethyleneSam, see Patent US3318891.

Ritter

  • Guest
Pd(OAc)2 Wacker
« Reply #7 on: January 24, 2003, 05:39:00 PM »
This is as perfectly good a place as any to disseminate the fact that when ISOsafrole is oxidized with t-butylhydroperoxide/Pd(OAc)2 no reaction takes place according to TLC.  It is a very interesting phenomenon because safrole gets oxidized to the aldehyde in very high, clean yields as proven by NMR yet isosafrole remains untouched under the same powerful oxidizing conditions.  This is one of the few rxns which has left me truely dumbfounded throughout the years.

Vibrating_Lights

  • Guest
Water
« Reply #8 on: February 05, 2003, 01:55:00 AM »
I don't know if this has been said before but the O comes from the water. I saw this in a ref recently.