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The Vespiary

The Hive => Methods Discourse => Topic started by: Jan1983 on June 17, 2002, 11:33:00 AM

Title: piperonylic acid
Post by: Jan1983 on June 17, 2002, 11:33:00 AM
Hi guys, again piperine piperidine piperic acid and so on,

here a question:

Can "piperonylic acid or the alcohol" also be used as a source for piperonal ?

Greets
Title: no
Post by: OB1KNoBee on June 18, 2002, 01:39:00 AM
Don't think so... stick to the sure thing.
GOOD GOOD
Title: The alcohol can be oxidized to the aldehyde ...
Post by: PrimoPyro on June 18, 2002, 04:56:00 AM
The alcohol can be oxidized to the aldehyde (which is piperonal) and technically LAH could reduce the acid (an ester of it) to the alcohol, ready for oxidation. But the practicality of this is very small.

The piperonyl alcohol would be a good source if it was cheap for you to get.  :)

                                                    PrimoPyro
Title: The alcohol: 100 g = 45€ cheap enough ?
Post by: Jan1983 on June 18, 2002, 07:33:00 AM
The alcohol:

100 g   =  45€

cheap enough ?

what can be used to oxidise the stuff ?? KMnO4 ? H2O2 ?

anyone has ref's ?
Title: UTFSE!
Post by: Antoncho on June 18, 2002, 11:35:00 AM
Fe(NO3)3




Antoncho
Title: Haha
Post by: PrimoPyro on June 18, 2002, 02:25:00 PM
We so very rarely here that tone from you, Antoncho.  ;D

As Antoncho says, ferric nitrate is the known method here. I bet cupric acetate with ammonium nitrate oxidation would work as well without overoxidation. It is a very gentle reducing agent.

KMnO4 will very likely yield the carboxylic acid. I don't know how H2O2 would fare at all, personally. I myself would stick with ferric nitrate since it has been documented here.

Reduction of the acid ester with LAH to the alcohol, then oxidation to the aldehyde, is not worth all the effort just for some piperonal. LAH is damn expensive, and should be saved for more important steps, i.e.reduction of nitrostyrenes etc.

                                                 PrimoPyro
Title: Another way
Post by: Antoncho on June 18, 2002, 06:28:00 PM
I forgot to mention that for those who, unlike swim, aren't financially challenged :) , PtO2 and oxygen is the best possible way. A very general and selective/high-yielding oxidation.


Antoncho

P.S. Primo:  ;)
Title: Cupric/ammonium nitrate
Post by: terbium on June 18, 2002, 07:11:00 PM
I bet cupric acetate with ammonium nitrate oxidation would work as well without overoxidation. It is a very gentle reducing agent.
Any reputable references to this procedure? I was under the impression that it was just someones pipe dream.
Title: The references I have seen on that oxidizing ...
Post by: Rhodium on June 18, 2002, 07:42:00 PM
The references I have seen on that oxidizing system deals with the oxidation of hydroxyketones to 1,2-diketones - I don't know its scope outside this.
Title: Arg
Post by: PrimoPyro on June 18, 2002, 08:51:00 PM
My references for that would be in TFSE, in posts that represent it as fact rather than novelty. I hate when TFSE is wrong or incomplete.  :(

                                                PrimoPyro
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