Remove aldehyde moiety (wrong word?) from aryl compound

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Presuming I have 3,5-dimethyl-4-nitro-benzaldehyde, and what I want is 2,6-methyl-nitrobenzene (same molecule, minus the -COH) is there a straightfortward way to do this conversion? Oxidizing it away seems risky: I don't want the -CH3 groups to go all -COOH on me, but I'm not an experienced enough as an O-chemist to know other ways to "address" an unwanted-aldehyde problem.

Any suggestions gratefully accepted.

BTW: Not interested in any help from the illicit-pharmaceuticals quadrant. My life is complicated enough without dabbling in anything illegal. :)

Thank you, and happy holidays 2017!
-Jeff
 

Discussion

JeffEvarts said:
2,6-methyl-nitrobenzene

That nomenclature is not correct.

JeffEvarts said:
Oxidizing it away seems risky: I don't want the -CH3 groups to go all -COOH on me,

I don't think mild oxidation will oxidise -CH3; something like PCC or [Ag(NH3)2]NO3 might work.
 
Thanks for your reply!
Sorry about the nomenclature. Please tell me the correct term so I can use it in the future.

I see "silver ammonium nitrate" (AgN2H4O3) But not the complex you list. What's the name for that compound?

Lastly, Pyridinium Chlorocromate ( which is the PCC I am familiar with) is the "kinder, gentler" chromic acid, and generally converts alcohols TO aldehydes.

I want to make sure I'm being clear: I'm trying to take a substituted benzene (1:nitro,2:methyl,4:aldehyde,6:methyl) and convert it to (1:nitro, 2:methyl, 6:methyl) by removing the aldehyde at position 4. If oxidation is the way to go, please let me know. If there's a better way to do it, please let me know.

Thanks Buffu
 
Argh... nvm on the nomenclature.

2,6-dimethyl-nitrobenzene.

-Jeff
 
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JeffEvarts said:
I see "silver ammonium nitrate" (AgN2H4O3) But not the complex you list. What's the name for that compound?

Tollens reagent.

TeethWhitener said:
Cannizzaro reaction then decarboxylation?

I think concentrated base in Cannizzaro will eat the methyl group also.
 
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In an effort to clarify, a diagram may be worth a thousand posts.

Reaction diagram: left, Have, 3,5-Dimethyl-4-nitrobenzaldehyde, a benzene ring with two methyl groups, a nitro group NO2 and a CHO aldehyde; right, Want, 2,6-Dimethyl-nitrobenzene, a benzene ring with two methyl groups and NO2 with no aldehyde.


Buffu and Teethwhitener have suggested some stronger and milder oxidization reactions. (Thank you!)

Any help with this reaction would be greatly appreciated.

-Jeff
 
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  • Reaction diagram: left, Have, 3,5-Dimethyl-4-nitrobenzaldehyde, a benzene ring with two methyl groups, a nitro group NO2 and a CHO aldehyde; right, Want, 2,6-Dimethyl-nitrobenzene, a benzene ring with two methyl groups and NO2 with no aldehyde.
    Rxn1.png
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Buffu said:
I think concentrated base in Cannizzaro will eat the methyl group also.
I seriously doubt this will happen in the absence of an oxidizer (cf. toluene pKa ~ 41). The advantage of Cannizzaro is that it’s oxidizer-free. The disadvantage is yield.
 
TeethWhitener said:
I seriously doubt this will happen in the absence of an oxidizer (cf. toluene pKa ~ 41). The advantage of Cannizzaro is that it’s oxidizer-free. The disadvantage is yield.

So to be clear, you're suggesting a Canizzaro reaction to produce the alcohol and the carboxilic acid, separating out the acid, and... heating with a strong alkali to drive it off as carbon dioxide? This should leave the methyl groups in place?
 
JeffEvarts said:
So to be clear, you're suggesting a Canizzaro reaction to produce the alcohol and the carboxilic acid, separating out the acid, and... heating with a strong alkali to drive it off as carbon dioxide? This should leave the methyl groups in place?
Yes. You sacrifice yield for a non-oxidizing environment.