Sciencemadness Discussion Board

o-iodoaniline

jcjones8 - 6-4-2015 at 08:59

how would you oxidize o-iodoaniline to o-iodonitrosobenzene.


[Edited on 6-4-2015 by jcjones8]

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Chemosynthesis - 6-4-2015 at 09:24

You should probably read the forum guidelines on proper places to post, after attaining a deeper understanding of chemical nomenclature (oxygens) and functional groups.

jcjones8 - 6-4-2015 at 09:47

nitroso... am i qualified enough to get an answer now?

szuko03 - 6-4-2015 at 09:51

Only if you can point out the alleged "second oxygen" on an amine ;)

Edit... Ah should read "Nitro" sorry I didnt see that I thought someones name was "nitroso" hahaha

[Edited on 6-4-2015 by szuko03]

Chemosynthesis - 6-4-2015 at 10:13

Quote: Originally posted by jcjones8  
nitroso... am i qualified enough to get an answer now?

Your editing your post to remove all references to the "one oxygen on" an amino group still don't put it in the "Beginnings" section, nor does the random word "nitroso" as a response.

Can you ask a real chemistry question? Not an unreasonable "qualification" to expect from someone if they read the forum guidelines.

jcjones8 - 6-4-2015 at 10:19

i didn't know people couldn't handle an informal question so i changed it so people wouldn't cry about some nomenclature.

Nicodem - 6-4-2015 at 11:02

There are numerous examples of N-oxidation of anilines to nitroso and/or nitro derivatives. The N-oxidation is step-wise enough for giving good selectivity for the nitroso intermediate under proper conditions. Most methods involve hydrogen peroxide or persulfates in the presence of heteropolyoxometalate catalysts. Here are some references with the simplest methods (using easily available catalysts):
Synthesis, 2004, 706-710; Synlett, 2008, 967-970; EP1099683.

SeO2 or organoselenium catalysts with H2O2 can also be used: European Journal of Organic Chemistry, 2007, 4431-4436.

mCPBA alone is also reported to work: Journal of Labelled Compounds and Radiopharmaceuticals, 1993, 33, 739-746.

Actually, the only reference that I could find for the N-oxidation of o-iodoaniline uses mCPBA. It is a dissertation from 2008 by D. B. Guthrie. Luckily for you, Chemical Abstracts abstracted the experimental for this reaction (CA 152:74517):
Quote:
The crude nitroso compound: In a round bottom flask fitted with an addition funnel, 2-iodoaniline (5.48 g, 25.0 mmol) was dissolved in CH2Cl2 (125 mL) at 0 °C with stirring. To this, a solution of 77 % w/w m-CPBA (9.06 g, 52.5 mmol) in CH2Cl2 (250 mL) was added dropwise over 1 hr at 0 °C. Immediately after addition was complete, the mixture was successively washed with saturated aqueous NaHCO3 solution (3 x 400 mL) and brine (400 mL), dried over MgSO4, filtered, and concentrated by rotary evaporation. The crude nitroso compound was immediately used in the next reaction without further purification.


It does not mention what was the purity or selectivity for the nitroso vs. nitro and iodoso compounds.

Chemosynthesis - 6-4-2015 at 11:23

Quote: Originally posted by jcjones8  
i didn't know people couldn't handle an informal question so i changed it so people wouldn't cry about some nomenclature.

Your "informality" was not remotely chemically correct, and so your question was nonsensical, and thus unanswerable. Despite the apparent challenge for you, it's really not that challenging for us to generally expect people to understand an amino group has no oxygens. If you can't do your own literature research, maybe you should learn to put up with people acting according to forum guidelines and scientific nomenclature (in the guidelines) where you post. You could have just named the product and reactant, drawn them both instead of just the product, or used your functional groups correctly. Specifity and accuracy aren't formalities in science.... They're requirements.

Again, you should learn what an amino group is, a nitroso, and then a nitro before you get upset at nomenclature you can't use. They have very real meanings with physical and chemical differences that can be dangerous to confuse. What you said originally was something like "take an amine with two oxygens and turn it into a nitro with one" or "take an amine with one oxygen and oxidize it into a nitro." You seem to want to turn an amine into a nitroso group, but can't possibly expect us to help you without expressing yourself intelligibly. Asking for clarification is hardly unreasonable, especially since you must have felt the criticism valid enough to edit your posts.

[Edited on 7-4-2015 by Chemosynthesis]