Remove aldehyde moiety (wrong word?) from aryl compound

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JeffEvarts
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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
 
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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.

Rxn1.png


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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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.