Anodic Decarboxylation of 3-phenylpropanoic acid -> n-propylbenzene
I was wondering if anyone has any information on work that has been done in the area of anodic decarboxylation or otherwise known as the kolbe
electrolysis/reaction? (Most papers I have read date back to the 60's)
Basically I just want to know if it has a higher efficiency now (In the case of 3-PPA -> n-PB your talking 411mg (not even all n-PB) from 2.89g)
and whether it even works at all.
Another problem I foresee is if n-propylbenzene was the desired product and 2-phenylethyl acetate was also formed, does anyone have a solution as to
how you could separate them out of this heterogenous oil?
There has been some previous discussion on this topic some time ago and it's implications but the site that these discussion were on is no
longer.
Any help on this would be greatly appreciated (a.k.a. I would feel more confortable making the investment into power supplies, lab grade platinum
electrodes & wires, etc, if I knew it was actually going to work)
An extract from the Bonner paper on this reaction published in J. Org. Chem. in Feb, 1964 has been provided for your consideration. Thanks guyz.
Kolbe Electrolysis of 3-Phenylpropanoic Acid in Acetic Acid (Anodic Decarboxylation)
-A solution of 3-phenylpropanoic acid (2.89 g.) and sodium acetate (1.43 g.) in acetic acid (25 ml.) was electrolyzed for 21 hr. (0.2 amp., 8
f./mole). The mixture was treated with excess ammonium hydroxide and the basic solution was extracted thoroughly with ether. The extracts were washed,
dried, and evaporated to yield 534 mg. of neutral, amber oil. This was chromatographed on 50 g. of silicic acid, with ether as eluent, affording 411
mg. of clear oil, which was examined by gas chromatography and retention times showed that n-propylbenzene and 2-phenylethyl acetate were the products
present
p.s. I intend on scaling this reaction up also which I couldn't see being a problem but if anyone wants to comment on this also would be greatly
appreciated.
[Edited on 5-4-2005 by 600538411]
[Edited on 5-4-2005 by 600538411]
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