[Meter]

Hello.

I'm working on a project where I have to substitute a dialdehyde. Since the molecule is symmetrical, I can't selectively react the aldehydes.

Does a process exist in which a reagent will react with both aldehydes, but result in two different aldehyde derivatives? The idea is that each aldehyde derivative would be different and thus possibly enable future regioselectivity I'm being vague as I don't know how much I'm allowed to disclose about the project, but I'll attach a schematic to show you the idea of what I'm trying to achieve.



Right now we're just reacting half molar equivalent amounts to achieve a statistical yield.

[rolnor]

How do you react A and B, if they are nucleophiles you would get an alcohol?
I see no way to selectively protect one aldehyde, even worse if you dont define the chain between them.
If you have a alkene with one aldehyde group you can do the manipulation of the aldehyde and then cleave the double bond with OsO4/NaIO4 to get the other aldehyde. You can also have a 1,3-dithiane or acetal similar.

[wildfyr]

Hmm... what about using the bisulfite adduct trick in as "organicky" a solvent as you can. Its likely the molecule will precipitate out when just one of the aldehydes is converted to the salt, and once its out of solution its less likely the other aldehyde will also react to make the bis-salt.

Fiddling with the cation could help make things crash out more aggressively if sodium  bisulfite isn't doing it.

If I just created some awesome new IP send me a PM lol.

[Meter]

Hmm... what about using the bisulfite adduct trick in as "organicky" a solvent as you can. Its likely the molecule will precipitate out when just one of the aldehydes is converted to the salt, and once its out of solution its less likely the other aldehyde will also react to make the bis-salt.

Fiddling with the cation could help make things crash out more aggressively if sodium  bisulfite isn't doing it.

If I just created some awesome new IP send me a PM lol.

Honestly, that sounds pretty smart. My original thought was that maybe one could engineer a molecule such that it its onto the dialdehyde like a hand in a glove where where the "pinky" and the "thumb" correspond to the A and B part. Obviously this might be a lot more trouble than it's worth, considering using a half equivalent amount works perfectly fine and you can reuse leftover unreacted dialdehyde.