njl
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Leuckart reaction with oxalic acid
Would oxalic acid work as a substitution for formic acid as a reducing agent in the leuckart reaction? Formic acid has the advantage of being oxidized
to CO2 but apparently oxalic acid is a stronger reducing agent.
P.S. Searched for this question but didn't find naything, sorry if it's a repeat
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unionised
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No.
There's no hydride to transfer.
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clearly_not_atara
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However, there is apparently an oxalic acid Eschweiler-Clarke:
https://www.researchgate.net/profile/Paul_Kosma/publication/...
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Corrosive Joeseph
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https://chemistry.mdma.ch/hiveboard/novel/000497428.html
/CJ
Being well adjusted to a sick society is no measure of one's mental health
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unionised
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"Primary and secondary amines are N-methylated by a mixture of paraformaldehyde..."
Just for a start, if you have paraformaldehyde, you can make formic acid.
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clearly_not_atara
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You can also make formic acid from oxalic acid, which I was going to recommend but I thought it was too obvious. But what's the best way to make
formic acid from paraformaldehyde?
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njl
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@All thank you for responses.
@Atara depends on where you are/what you have but basically hydrolyze paraformaldehyde to get a concentrated aqueous solution and then oxidize over
KMnO4. Using KMnO4 has the advantage of leaving you with the formate salt after oxidation, so you can easily purify and then recover the acid with
HCl. The reason I didn't mention the oxalic acid --> formic acid prep is because I don't have any glycerin at the moment.
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unionised
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Quote: Originally posted by clearly_not_atara  | | You can also make formic acid from oxalic acid, which I was going to recommend but I thought it was too obvious. But what's the best way to make
formic acid from paraformaldehyde? |
Hydrolysis to formaldehyde by dissolution in hot water, then this
https://en.wikipedia.org/wiki/Cannizzaro_reaction
to get formate.
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unionised
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I'd avoid the oxidation by permanganate since it also attacks formic acid.
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njl
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I agree the Cannizzaro reaction looks better. I don't have any experience with it which is why I didn't mention it.
@unionised wouldn't the potassium salt be less prone to oxidation to oxidation?
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unionised
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Probably, but paraformaldehyde is cheaper than permanganate.
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S.C. Wack
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One would add peroxide first, unless small amounts of methanol are needed.
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