Author Topic: p-nitrotoluene  (Read 2050 times)

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El_Zorro

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p-nitrotoluene
« on: October 19, 2002, 03:16:00 AM »
Ok, if a bee wanted some p-nitrotoluene, what would his/her best way of getting it be?  I know if toluene is nitrated with conc. H2SO4/HNO3, it results in a mix of o- and p-nitrotoluene.  How can they be separated?  Which product is more prevalent?  Would it be worth it to get the resulting p-nitrotoluene?

I guess this part is more suited to the Aqcuisition forum, but is p-nitrotoluene watched at all?  Can it be purchased easily in the US?  Or do suppliers connect it with TNT?

Who is that masked man?

Rhodium

  • Guest
They can be separated through fractional ...
« Reply #1 on: October 19, 2002, 03:34:00 AM »
They can be separated through fractional crystallization. The procedure is either in cheapskate's document on quaalude manufacture on my page, or posted somewhere at the hive.

El_Zorro

  • Guest
Would o-nitrotoluene react the same as ...
« Reply #2 on: October 19, 2002, 11:04:00 PM »
Would o-nitrotoluene react the same as p-nitrotoluene in the nitrotoluene-->toluhydroquinone reaction?

Who is that masked man?

Rhodium

  • Guest
What is your definition of "react the same"?
« Reply #3 on: October 20, 2002, 12:16:00 AM »
What is your definition of "react the same"? That isn't especially descriptive. Also please link to descriptions of lesser known reactions when referring to them.

Chromic

  • Guest
Clarifying the question
« Reply #4 on: October 20, 2002, 07:37:00 AM »
If you're asking if 2-methyl-1,4-hydroquinone will result from an tautomer fairy waving her wand on a 2-nitrotoluene intermediate during the reduction, that is, a reduction such as of the 4-nitro variant:



... why did you just go ahead and ask that question?

To which, I'm sure some people more knowledgeable than I will have answers to. My intution says yes--due to electronic similarities between the 2- and 4- positions (based on the thought that _if the reduction goes past the substituted aniline_ the two hydroxylations would have to occur para to each other, and the substance formed would have to be 2-methyl-1,4-hydroquinone... but hey, if it doesn't, then you'll have some o-toluidine ready to make some 'ludes..)

... although my gut feeling seems to indicate that regardless of the answer, I really doubt you're going to get anywhere close to DOM along this route... it appears to be a long, ardous road starting from toluene! (just look at the efforts of other bees with making 2C-B starting from hydroquinone, which IMHO, seems to be easier to make)

And Rhodium, why didn't you answer what you thought he was asking? There seems to be only two mentions of this particular quinone on your page, one of its preparation the other of its use.

Perhaps I'm grumpy!  ::)

Rhodium

  • Guest
The strange reactions of nitrotoluenes
« Reply #5 on: October 20, 2002, 09:12:00 AM »
First of all, I'm somewhat grumpy myself today after finding out that I had accidentally deleted all of my research findings and lab notes which pointed towards a novel method of performing LAH reductions which gave 20% higher yields in a fraction of the time traditionally needed.

Second, I am tired of having to use the search engine either at my own site or here to answer people's questions just because they are too lazy to provide a link to the post or document they are referring to (and to ask the question, they must recently have had the document/post open in their browser window, so it would have been an easy task to copy and paste the URL/Post No). That work should be performed by the person wanting an answer and not by me... In the above question, not even the method for performing the reaction is mentioned, just the starting material and the product. As noone can expect me to have memorized the reaction conditions, mechanism, scope and limitations of every reaction featured on my page, especially not the more exotic ones, they should *know* that I had to look it up before I could answer.

To finally get back to the topic of the thread, I am not sure that it will work, as the reaction products include not only the toluhydroquinone, but also 4-aminotoluene - hinting that the aniline might not be an intermediate in the reaction, and if it's not, I have no idea about the reaction mechanism. Note: This only means that I have no idea if it will work, and not that it won't work.

However, there is still hope, as o-nitrotoluene can be reduced with lots of reagents (including Fe/HCl) to o-toluidine (2-aminotoluene), which can be oxidized to toluquinone with sodium dichromate, as described in the same document on my page. Reducing toluquinone to toluhydroquinone is an easy task too, and can be done in a variety of ways, using for example Zn/HCl or Na2S2O4/NaOH, also detailed in the document.


Chromic

  • Guest
Grumpiness
« Reply #6 on: October 20, 2002, 01:57:00 PM »
At least you have a reason/excuse to be grumpy. My neurotransmitters are just out of whack from excessive drug use.  :(

These are very unique reactions. It wasn't until after using the search engine that I understood how they were a means to DOM (I always thought your quinones document was just about making oxidation reagents for the Wacker)... if no answer precipitates from this discussion, at least I got a bit of understanding out of it.  :)

moo

  • Guest
2,5-DMBA
« Reply #7 on: October 20, 2002, 03:04:00 PM »
2,5-dimethoxytoluene, from methylation of 2,5-dihydroxytoluene, can also be oxidised to 2,5-dimethoxybenzaldehyde with MnO2, Fe/Cu/H2O2, Fe/Cu/persulfate and some other methods.

El_Zorro

  • Guest
Yes, I was referring to the ...
« Reply #8 on: October 20, 2002, 09:01:00 PM »
Yes, I was referring to the nitrotoluene-->toluhydroquinone reaction via Al and H2SO4.

https://www.thevespiary.org/rhodium/Rhodium/chemistry/quinones.html



It seems to me that o- and p- nitrotoluene would both form the same hydroquinone, provided the o- variety forms the para hydroxy's as well.  I was thinking that this could be an easy and relatively cheap way to large amounts of 2,5 DMB, once the hydroquinone is methylated and the methyl group is oxidized to the aldehyde.  I guess someone might even do an aldehyde addition on the methylated hydroquionone to go for DOM.

Who is that masked man?

moo

  • Guest
It seems to me that o- and p- nitrotoluene would ...
« Reply #9 on: October 20, 2002, 09:26:00 PM »
It seems to me that o- and p- nitrotoluene would both form the same hydroquinone, provided the o- variety forms the para hydroxy's as well.

How come? I wouldn't be so sure about it but really don't know either.

Rhodium

  • Guest
entheo-quinones
« Reply #10 on: October 20, 2002, 09:28:00 PM »
FYI, the synthesis of 2C-D and DOM from toluhydroquinone in 4-5 relatively high-yielding steps is detailed on my page.

Chromic

  • Guest
Hydroxys
« Reply #11 on: October 20, 2002, 10:01:00 PM »
The hydroxys would orient para- to each other, as they're a very strong activating para-directing group. Who knows if the reduction would go past 2-aminotoluene though. Where's foxy2?  :)

El_Zorro

  • Guest
I guess the real point of this post was to find ...
« Reply #12 on: October 20, 2002, 10:19:00 PM »
I guess the real point of this post was to find out if it would be worthwhile to separate p-nitrotoluene from o-nitrotoluene when trying a synth of toluhydroquinone.  Does anyone know for sure if they would both react to form the hydroquinone?

I guess in the workup for that reduction, a bee might just extract everything out of the post reaction mix with a NP, then give it a couple acid washes to remove all of the amino compounds, right?

Who is that masked man?

Rhodium

  • Guest
Reaction diagram
« Reply #13 on: October 21, 2002, 12:41:00 AM »
Al/H2SO4 treatment of:

4-nitrotoluene: toluhydroquinone + p-aminotoluene
2-nitrotoluene: o-toluidine + (toluhydroquinone?)

Dichromate treatment, followed by reduction:

o-toluidine: toluhydroquinone
p-aminotoluene: (toluhydroquinone?)

As you see, you only need to perform two reactions to find out if all of the starting materials and/or byproducts can be used to form the desired final product. If they can't, you will at least know which of the by-product you need to discard.

El_Zorro

  • Guest
Re: Dichromate treatment, followed by reduction: ...
« Reply #14 on: October 21, 2002, 07:53:00 AM »

Dichromate treatment, followed by reduction:




Dichromate?  I don't follow.  But I was thinking that the Al/H2SO4 treatment of the nitrotoluene could be a useful reaction.  You could run the reaction, then steam distill out the toluidine for qualuude manufacture, then extract the remaining post-reaction mix, do an acid wash, then evap the solvent for the hydroquinone.


Who is that masked man?

Rhodium

  • Guest
In the quinones document, the reaction described ...
« Reply #15 on: October 21, 2002, 10:55:00 AM »
In the quinones document, the reaction described directly above the Al/H2SO4 procedure shows how to react o-Toluidine with dichromate to form toluquinone.