07-03-02 01:33
No 328258
      O2 wacker (alkyl aryl ether isomerization?)  Bookmark   

I don't know if this is true but some info was relayed pertaining to wacker oxidations.
Something like isomerization of methylenedioxy ether to the  2,3 positional isomer being the main problem with getting a wacker oxidation to work.
Does this really happen?
I did'nt think so, but some input from some of you more educated bee's would be appreciated.
(Stoni's sexual toy)
07-03-02 01:37
No 328260
      No, the problem is that the alkene is isomerized.  Bookmark   

No, the problem is that the alkene is isomerized.

I'm not fat just horizontally disproportionate.
(Hive Bee)
07-03-02 01:48
No 328262
      Yeah it sounded like B.S.  Bookmark   

Yeah it sounded untrue  to me, never hurts to ask though.
(Hive Prodigy)
07-03-02 05:19
No 328297
      To Osmium  Bookmark   

What is the product of the Wacker-oxygenated phenylpropene? Is it the propiophenone instead of the phenylacetone?
(Hive Bee)
07-03-02 06:16
No 328304
      From what i've read  Bookmark   

And this was verified via NMR, that a typical wacker is 85%
Phenylpropanone, %15 phenylpropylaldehyde.
No propiophenone is formed although isosafrole is a by-product.
You can add inhibitors (free radical i think not sure though) like hydroquinone to prevent aldehyde formation, even read that this increases yeilds in alcoholic wackers and reduces temperature sensitivity, it's a patent, have it somewhere.
You know how patents are with thier inflated sometimes bogus claims though.
(Hive Bee)
07-09-02 08:20
No 330413
      Using Pd(NH3) 4 Cl 2 will inhibit the ...  Bookmark   

Using Pd(NH3)4Cl2 will inhibit the isomerization.  Alkyl nitrites also inhibit the isomerization, as hardly no isosafrole is produced by a nitrite wacker.