Sciencemadness Discussion Board - hydroquinone/picric acid

hydroquinone/picric acid

YT2095 - 8-7-2006 at 08:48

as the quinone is basicly Phenol with an extra OH at 5, it seemed reasonable to me that picric acid shouldn`t be all that dificult to make from it (less work than some of the crude ASA synths).

I worked from the starting point of having my pure ASA and been heated with conc H2SO4 liberating the acetic acid etc...

and just added conc H2SO4 to 50mg of Quinone.
I let that stand for most of the afternoon as I had work to do, when I came back there was a tiny tiny darkening of the soln and the Quinone was all foating on the top.

I added a few crystals of KNO3 (about 200 mg) to the approx 3ml of soln, no reaction at 1`st and then slowly the NO2 evolved, the liquid layer started to go yellow and the needle like crystals took on a black(ish) color.
there was no noticable heat created (to the hand) and certainly no runaway nitration.

after 15 mins of standing with a stir every few mins, the liquid layer is getting more Orange and there`s less Black crystals.

my questions are...

1) why did they go black?
2) is this in anyway a Viable method of Picric acid formation as I thought it would be?
3) if it Does form Picric acid, what`s the best way to dispose of it (and Don`t say blow it up! that exactly what I Don`t want to do).

DeAdFX - 8-7-2006 at 08:54

Styphnic acid has two hydroxyl's if I remember correctly but is made from rescorniol(sp) and not hydroquinone. Maybe you have a different isomer of styphnic acid?

YT2095 - 8-7-2006 at 09:17

if mem serves me corectly I think the propper name is something like 1,4 para benzene diol.
basicly it`s just Phenol with another OH group on the opposing side of the ring.
catechol`s also similar but that`s like 1,2 benzene diol, that has the 2 OHs side by side.

(I`m working from mem, and although corrections are welcome, the above has little relevance, the 2 OH`s Do though).

I`m not sure Quinone can Have an Isomer in the way of Cis Trans anyway?

non the less, the soln is now a deep orange, and strongly ressembles picric acid in color. I`m still curious at to the questions I posted.

The_Davster - 8-7-2006 at 11:25

Most nitroaromatics are yellowish in colour. I don't believe you have formed picric as that would mean loss of an OH group, which is not so easy. You likely have a mixture of nitrated hydroquinone products mainly di and mono, with perhaps a small ammount of tri.

[Edited on 8-7-2006 by rogue chemist]

YT2095 - 9-7-2006 at 00:28

Thanks, and yes, that makes sense, sadly I think I`ve left it a little too long now as the contents are entirely Black.
the Quinone with the Conc H2SO4 and KMnO4 also went black over night, the only reasonable reaction was the Quinone in water with Iodine crystals.

I`m sure I`ll find something interesting to do with this chem eventualy, other than make it go Black!

Marvin - 9-7-2006 at 09:37

Hydroquinone is very easily oxidised and tends to fall apart. If you think how much more reactive and easily oxidised phenol is than benzene, add an extra OH, then factor in the stability of the conjugation of the quinone oxidation product...

Nicodem - 9-7-2006 at 12:32

Quote:

Originally posted by YT2095
as the quinone is basicly Phenol with an extra OH at 5, it seemed reasonable to me that picric acid shouldn`t be all that dificult to make from it (less work than some of the crude ASA synths).

Quinone is not a phenol and has no OH groups. I assume you mean p-benzoquinone as that is the only quinone shortened to simply "quinone". Or perhaps you have confused quinone with hydroquinone which is indeed a phenol, but "4-hydroxyphenol" and not 5-.
Anyway, there is no reasonable synthetic route to turn either quinone or hydroquinone to picric acid.

Quote:

1) why did they go black?

I don't understand what you mean. Quinone is already black (well it can be anything from dark brown to dark green). In case you used the colorless hydroquinone (since you talk about "needle like crystals" and don't mention them having a color) then it is obvious they went black as all kind of shit happened to them. Hydroquinone easily oxidizes to quinone and other tarry crap (all black), especialy in the presence of HNO3 (to crap mostly).

Quote:

2) is this in anyway a Viable method of Picric acid formation as I thought it would be?

No, check the structure of p-benzoquinone, hydroquinone and picric acid. If you would have enough knowledge of organic reactions you would realize that immediately by yourself.

chemoleo - 9-7-2006 at 14:58

Of course he meant hydroquinone.

What is interesting that resorcinol is 3-hydroxy phenol, so very similar to hq. From this stypnic acid can be made like a charm.

I was thinking, perhaps the best way to make energetic derivatives form this is to first methylate the hydroxyquininone, to i.e. 1,4 methoxy benzene using any of the standard methylating agents. This then could be nitrated. The question is, since both -OCH3's are activating, would one get the tetranitro derivative of 1,4 methoxy benzene, or always and exclusively, either the 2,5 or the 36 di-nitro derivatives? or only 2, 6 and 3, 5 dinitro derivatives?

So yes there are things that can be done with hydroquinone.

YT2095 - 10-7-2006 at 00:37

Fascinating! I have 1,2 benzene diol also (or is it worded; 2, hydroxyphenol?) that sounds very similar too.
I`m trying to teach myself a little Organic Chem with the aid of a few good text books and some basic compounds, so I`m a relative Newb in this area.
I wanted Picric acid as it`s used as a dye (or at least was once upon a time), ultimately I`de like to work towards making Azo Dyes and some interesting esters.

did anyone know that trinitro methylbenzene is actualy used in some perfumes!

anyway, I`ll try the same experiments with the pyrocatechol and see what happens as well as look up this Stypnic acid.

The_Davster - 10-7-2006 at 05:04

Quote:

Originally posted by YT2095

did anyone know that trinitro methylbenzene is actualy used in some perfumes!

You sure about that? That is plain ol TNT, and with its toxicity and staining ability(similar to nitrophenols but not as strong IIRC) I am surprised it is in anything that would get put on the skin.

[Edited on 10-7-2006 by rogue chemist]

YT2095 - 10-7-2006 at 05:56

Yup 100% certain, it`s used as a Musk compound.

"The discovery of the first synthetic musks is a by product of research on explosives. In 1888, Albert Baur, in the process of searching for new explosives noticed that the product of reaction of trinitrotoluene (TNT) and tert-butyl halides produced a pleasant odour. Musk Baur became the first synthetic musk, classified under the nitro musks category. In 1894 he produced Musk Ketone, which was said that resemble the natural musk fairly closely and until quite recently was among the popular perfume ingredients. The nitro musks (Musk Xylol, Musk Ketone, Musk Tibetene, Musk Ambrette, Moskene) possess a warm, powdery scent, with an ambery and animalic overlay. The sensual warmth of Musk Ketone as well as other nitro musks pervades the base of Chanel No. 5 (1921) and of many other fragrances from that period. "

Taken from: http://boisdejasmin.typepad.com/_/2005/11/fragrance_ingre.ht...

there`s probably 100`s of other sources for a TNT Musk search too.

here`s another: http://www.matze-wormuth.de/musk.htm

[Edited on 10-7-2006 by YT2095]

Nicodem - 10-7-2006 at 07:29

Quote:

The question is, since both -OCH3's are activating, would one get the tetranitro derivative of 1,4 methoxy benzene, or always and exclusively, either the 2,5 or the 36 di-nitro derivatives? or only 2, 6 and 3, 5 dinitro derivatives?

The only reference for 2,3,5,6-tetranitro-1,4-dimethoxybenzene is J. Chem. Soc. C, 1967, 1235 - 1238. They nitrated 2,3,5-trinitro-4-methoxyphenol
or 3,5-dinitro-4-methoxyphenol in HNO3 (d = 1.4 g/ml) at 70°C. Then they methylated the resulting 2,3,5,6-tetranitro-4-methoxyphenol with dimethyl sulphate.
The paper is attached.

1,4-dimethoxy benzene can be mononitrated and dinitrated (forming a mixture of 2,5 and 2,3 dinitro regioisomers). I have not seen any reference for trinitration but I have never searched anyway. Perhaps it might be even possible to tetranitrate it directly without extensive demethylation, but it seams like it has not been done yet.

Quote:

did anyone know that trinitro methylbenzene is actualy used in some perfumes!

Yup 100% certain, it`s used as a Musk compound.

If you would read the text you cited a bit more carefuly you would notice that there is no mention of TNT being used as a perfume. It only says that TNT was used as a reagent to prepare musk like smelling compounds.

[Edited on 10-7-2006 by Nicodem]

Attachment: J39670001235.pdf (598kB)
This file has been downloaded 981 times

YT2095 - 10-7-2006 at 07:44

I read and cited them Very carefully thank you, what part didn`t you understand?
it is (or at least was) used in perfume making. and no, no single perfume Ever is just a single compound, they use a base(s) to start with and then select the over-tones.

I fail to see your point here? Unless it`s one based upon nit-picking or semantics? I`m good at neither of those.

quicksilver - 10-7-2006 at 07:47

Govermental disposal of nitrated phenolsls is somewhat complex. Regulations differ but in general the material needs to be broken down as then disposed as a toxic waste. It is broken down at a waste facility designed for that purpose.

If the intention is to dispose of a small amount this could be accomlished by the addition of a chlorinated salt to a high concentration solution. But in a situation wherein there is concern for environmental issues and one is disposing of a large amount then any toxic waste facility would be appropriate for containerized nitrophenols. An addition of chlorobenzene to the completed tri-nitrated form will yield a non-explosive material that may be diluted and disposed of. I think you can find that in the PATR.

As a dye it has been found (and many who have experimented w/ PA will attest) that the higher the pH, the redder the material. An orange PA indicated that there exists a higher pH in the production. this can be taken to extremes and a "red-goo" material achieved. The issue here is that what some had thought to be a method of making PA non-explosive by raising the pH very high didn't work for the most part. I am not sure that all benzene-ring explosives behave like TNT but in that case the addition of an after productiion hydroxide will sensitize it!

YT2095 - 10-7-2006 at 07:56

Turmeric, another Dye found in the root of a certain plant will also dye clothes a remarkably similar color to PA, interestingly enough, it Also will go red the greater the PH. this can also happen Long after the item of clothing ahs been worn and washed a kazillion times, drop some NaOH on it for instance and Wallop, bright red

Sunlight tends to fade it though, so the next curry stain you get on your best T`shirt, shove it under a sunlamp for a while

neutrino - 10-7-2006 at 13:33

Quote:

The discovery of the first synthetic musks is a by product of research on explosives. In 1888, Albert Baur, in the process of searching for new explosives noticed that <b>the product of reaction of trinitrotoluene (TNT) and tert-butyl halides</b> produced a pleasant odour. Musk Baur became the first synthetic musk, classified under the nitro musks category. In 1894 he produced Musk Ketone, which was said that resemble the natural musk fairly closely and until quite recently was among the popular perfume ingredients. The nitro musks (Musk Xylol, Musk Ketone, Musk Tibetene, Musk Ambrette, Moskene) possess a warm, powdery scent, with an ambery and animalic overlay. The sensual warmth of Musk Ketone as well as other nitro musks pervades the base of Chanel No. 5 (1921) and of many other fragrances from that period.

It sounds like only a derivative of TNT is used, not the explosive itself.

Mason_Grand_ANNdrews - 11-7-2006 at 09:48

I wonder, this method will be most interestingly, "qiunone" to phenol. I`ve some way obtaining dipicric acid. This wil formed by the way of benzophenone but i`m not shure.

This will describe the method:
Prepare a solution Benzophenone in Methanol and to this a solution of NaOH will be added. This is dilluted with a large amount of 3% HCl to precipitate the benzophenol. I don`t know the result is slight soluble in water and this are right, at least a precipitation will be possible when the mix is cooled to 0 °C. I will calcultale the amounts later, possibly ethanol is used for this. The nitrated benzophenol should give 2,2`,4,4`,6,6`-hexanitrobenzophenol or dipicric acid.

1. the result is not slight solule in water
Prepare a mix of 500 ml 98% H2SO4 and 340 ml 70% HNO3 in a cold water bad. To this 20 g of benzophenol is careful stirred in and he mixture is than over a period of 4 hours stirred and slowly heated to 100 °C. to this 2000 ml cold water is added, the product is filtered and a washed with a large amount of water wich will remove the H2SO4 of the product. This will be similar to the process of 4-chloro-2,6-dinitrophenol and will use a little waste of H2SO4.

2. the result is slight soluble in water
240 ml of 98% H2SO4 and 340 ml 70 % HNO3 will be enough,
but the benzophenol is nitrated complete ? 1000 ml water is added to the cooled mix and the filtered result is washed with small portions of water.
To obtain a better result fuming concentrated H2SO4 is used. A nitrated result at lower temperatures between 62 to 68 °C should give a tetranitrate. The mixture is than cooled to room temperature, 1000 ml of cold water is stirred in and the result is filtered and washed with several small portions of cold water.
I belive it will work when the benzophenol is dissolved in the H2SO4 and HNO3 will be added to this. A possible way is when benzophenone is nitrated by step 1. or 2. and this will give dipicric acid by NaOH and MeOH .
I guess many interested explosives or similar methods of nucleophilic substitution will have a way that used dipicric acid. I`m looking for a simple way to obtain DPA by picric acid or other ways. Anyone have some thoughts to that ?

[Edited on 11-7-2006 by Mason_Grand_ANNdrews]

[Edited on 13-7-2006 by Mason_Grand_ANNdrews]

YT2095 - 11-7-2006 at 10:04

what color is Di-picric acid?

and is it any good as a Dye?

Explosives I can make IF I wanted to, but I have no desire or use for any. this is only Posted in the Energetic materials thread because that`s what it`s better known for, and I stand a better chance of a good workable synth.

Swany - 11-7-2006 at 11:13

Di-picric acid meaning 2,4 dinitrophenol? Or, a dimer/2 TNP molecules that have been mashed togeather?

It is used in dye manufacturing, like every other nitrocompound. I do not know of its dying properties, a MSDS may help. I suggest you look into azo and diazo compounds, perhaps aminoguanidine derivs. as well.

Everyone who frequents energetic materials tends to look elsewhere on the forum as well.

Mason_Grand_ANNdrews - 13-7-2006 at 08:57

I guess dipicric acid is yellowish. It was a vagary

only. I belive you will found nothing in MSDS. Exuse me, some errors was corrected. I will post something like this in energetic materials.
CAS-Nr. of benzophenone: 5350-57-2

[Edited on 13-7-2006 by Mason_Grand_ANNdrews]

Mason_Grand_ANNdrews - 15-7-2006 at 10:58

To the last post a small attachment which give the structure of dipicric acid or something like this what DPA is. I guess DPA will be obtained by a nitrophenol, 3-bromophenol in concentrated H2SO4 and HNO3 can give the result in figure 2.

dipicric acid.JPG - 17kB

woelen - 15-7-2006 at 13:13

Quote:

No, what you tell here is not true.

Quinone is lemon-yellow and in fact has a really beautiful color (and a disgusting phenol-like odor).

When hydroquinone (p-dihydroxybenzene) is oxidizing in acidic media, then quinone is formed. This quinone forms a complex with remaining hydroquinone. This complex, which has formula C6H4O2.C6H4(OH)2 is dark green. It also is called quinhydrone. Look at this site for more information on quinhydrone.

http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organisc...

When the quinhydrone is further oxidized, then the solution becomes lighter again, and finally you get a beautiful deep yellow solution of quinone (better: p-benzoquinone). On standing, crystals of quinone are separated from the liquid.

You can make quinone fairly easily yourself. I did this and I have a small sample of quinone at my home lab.

Dissolve some hydroquinone in as little as possible dilute sulphuric acid (conc. of acid is not critical).
Add a very small pinch of V2O5 (this is needed as catalyst).
Add NaClO3 (reaction takes 1 mol of NaClO3 for each 3 mols of hydroquinone), add excess NaClO3 (e.g. 1.5 times the stoichiometric amount). It probably also works with KClO3, but the disadvantage of KClO3 is its limited solubility in water.
Shake well every few minutes.

First the solution becomes very dark (due to formation of quinhydrone). On further shaking, the solution becomes bright yellow. This reaction takes a few hours and you need to shake a lot. It is very tedious, but the end result is very nice. You get many yellow crystals of quinone. If the liquid becomes warm during the reaction, keep it cool with cold water from a slowly running tap.

These crystals of quinone must be rinsed with a small amount of cold distilled water and then can be extracted and recrystallized from an organic solvent. IIRC correctly, I used diethyl ether, but a low boiling ligrion also should do the job. The resulting quinone is not really bright yellow, it is yellow with a brown tinge, but it is good enough for my purpose and experiments.

Beware: quinone is quite toxic and it has a really horrible smell. I keep my sample in a small plastic bottle, with a larger plastic bottle around it, and that bottle in a glass botlle. Only then I have not the horrible smell of this compound in my lab. Also, p-benzoquinone is very volatile and its vapor stains everything with a nasty brown/red color, which cannot be removed.

=======================================================

When hydroquinone is oxidized in alkaline solution by oxygen from the air, then you indeed get all kinds of black and tarry substances. This is totally useless crap, but it is quite interesting to see how a solution of hydroquinone in dilute NaOH quickly changes color.

Remarkably, when some sodium sulfite or sodium bisulfite is added, then the destructive oxidation by oxygen from air proceeds MUCH slower. Just try it. Dissolve some hydroquinone in water. Make two parts of this. To one part, add a solution of NaOH. To the other part, add a solution of sodium (metabi)sulfite and then add the NaOH and look at the difference. This stabilizing effect of sulfite is exploited in black and white photography, where hydroquinone is used as a developer.

[Edited on 15-7-06 by woelen]

Mason_Grand_ANNdrews - 18-7-2006 at 10:05

Why is that what i will tell not correct ? I guess there is no one way to obtain hydroxy results. I guess your link will descibes a method which the result will decompose until one hour, perhaps it will work when the filtrate will used for a other synthesis bevor it decmpose. I think it will work when the hydroquinone

is obtained by benzoquinone - MeOH/NaOH and the dryed result is used for somthing more but i`m not sure if the remainder of the sodium salt in the result will be bad and this will not work by benzoquinone.

woelen - 18-7-2006 at 22:42

I wrote that your remark is not correct, because hydroquinoine is not oxidized to tarry crap in acidic media and p-benzoquinone is not black/green, but lemon-yellow.

And it works what I described, because I have a sample of the yellow p-benzoquinone. I can put a picture over here of the stuff if you like.

In alkaline solution things are totally different. You indeed get black crap. What happens in alkaline solution is that the material is oxidized and condensed species are formed (multiple aromatic rings are connected through each other in all kinds of interconnections). The larger the condensed species, the stronger the color. IIRC with hydroquinone the color is brown/red, with catechol the color is green. At a certain point, the condensed species become so large that macroscopic particles are formed and that can be observed as very dark, almost black particles. These condensed partly oxidized species are totally useless. One cannot assign a certain formula to these compounds, in fact it is a very ill-defined mix of very large molecules. When this material is dried you obtain a dark brown powder, insoluble in water, which definitely is not p-benzoquinone, nor quinhydrone.

chromium - 18-7-2006 at 23:02

Btw this was Nicodem who described properties of quinone incorrectly.

Nicodem - 18-7-2006 at 23:19

Yes indeed.

I'm not going to claim any color for p-benzoquinone since it is a "cameleon" compound, however the p-benzoquinone*hydroquinone complex has a defined color, some kind of metalic dark blue. I remember a thread from another forum where there was a huge discussion on p-benzoquinone color. All kind of colors were proposed (including your yellow one) and at the end all gave up. If you got a yellow product it does not mean much since making it by a different published method or from another batch of hydroquinone would give a different color. For example, in our lab we have some technical grade p-benzoquinone which is brown or almost black and some p.a. quality that is some kind of a weird color in between dark yellow and dark green.

Madandcrazy or whatever nickname you now have, you should stop posting misinformation like that bullshit about "dipicric acid". I don't know why you do these things, but please keep in mind that some members might actually believe in all your fantasy compounds and procedures, which is irresponsible from your part. :mad:

YT2095 - 19-7-2006 at 00:39

well since I`m reasonably new to Organic chem, I find it quite amazing that the different properties of what at face value in empirical formula looks like 3 identical chemicals, Hydroquinone, resorscinol and pyrocatechol, are in fact so very different when it comes to the actual material itself. all by althering the positions of the OH from 2 3 or 4.

I`ve trien the pyrocatechol in Iodine water, there was little in way of a reaction at first, but left to stand for a week, there is now a deep purple (KMnO4 purple) stain on the inside of the tube where the liquid rests, the actual liquid itself is a purple/brown and no where near as deep in color as the stain, there`s also a Very distinct smell to it also, not at all unpleasant but very hard to describe, it`s sweetish and mildly resembles wintogreen(sp) ester?
it in no way behaved the same way as the hydroquinone did,

I certainly have much more learning to do, as this is a perfectly Fascinatinfg area of chem!

woelen - 19-7-2006 at 01:23

Quote:

Originally posted by chromium
Btw this was Nicodem who described properties of quinone incorrectly.

Good that you pointed out that one. My apologies towards Mason_Grand_ANNdrews.

As far as the color of p-benzoquinine is concerned, I have understood that it really is yellow, but all kinds of brown/green tinges can appear, due to impurities. The material is very prone to oxidation or decomposition and then it forms all kinds of highly colored compounds. It is a little like aniline, or p-aminophenol, which are colorless, resp. white, when very pure, but in practice these are brown due to all kinds of oxidized species, which are formed on contact with air.

@YT2095: Yes, the three dihydroxybenzenes are quite different, but resorcinol, the meta-form, is much more different than the other two. The other two can be oxidized very easily, due to their ability to form quinone-structures, while this is not possible with resorcinol. The latter compound hence is much more stable on storage and also in solution.

If you want really weird things, then try reacting the catechol with chromium compounds in alkaline medium (e.g. chrome alum). You'll get really beautiful colors, ranging from deep red, to bright oranges, but also blacks. Try the same with iron and copper salts. These compounds form MANY highly colored complexes with most transition metals. I have tried almost all combinations of Cu(2+), Fe(3+), VO(2+), Ni(2+), Cr(3+) and Co(2+) with hydroquinine and catechol in neutral and in alkaline solutions. Try it and be amazed by all these beautiful colors you obtain!
The chemistry behind all these things is amazingly complex. It is a combination of complex formation, redox reaction, and condensation of smaller molecules/ions to larger ones. Unfortunately, most of these are riddles to me, but the experimental outcomes are quite nice.
Most beautiful though is mixing a neutral solution of hydroquinone with a slightly acidified solution of ferric chloride or ferric sulfate and then adding a small amount of H2O2 and letting it stand. A 3D network of very thin metallic looking glittering wires and needles will be formed, which really looks amazing.

YT2095 - 19-7-2006 at 02:15

Quote:

Originally posted by woelen
mixing a neutral solution of hydroquinone with a slightly acidified solution of ferric chloride or ferric sulfate and then adding a small amount of H2O2 and letting it stand. A 3D network of very thin metallic looking glittering wires and needles will be formed, which really looks amazing.

I just tried that, it went Brown/black almost instantly and got very Hot!?

FeSO4 disolved in water then a droplet of sulphuric acid added.
then in another tube the HQ dissolved in water.
I mixed the 2 and there was no reaction, I then added a few drops of H2O2 and then it changed.
but I`ll let it stand a while and see what happens next.
my test tube rack holds 100 test tubes, so I still have plenty of room left to do other things whilst I wait

Marvin - 19-7-2006 at 04:27

"but also blacks"

Is black really a colour, or is it just too much of something else?

YT2095 - 19-7-2006 at 04:34

I think In my case with that last reaction it`s just Very bark brown with a hint of black, HQ seems such a delicate chemical and is very easily destroyed in what seems like Carbonised burned sugar looking liquid crap

well at least in My (possibly clumsy) hands it does *sigh*

the pyrocatechol seems alot more stable and will take quite a bit of punishment before it craps out.

nevermind, I`ll get the hang of it eventualy!

caramel anyone?

[Edited on 19-7-2006 by YT2095]

Mason_Grand_ANNdrews - 30-7-2006 at 08:50

Exuse me, you are right, some of my posts was not correct in the topic and i would give any comnents to the dipicric acid synthesis. I guess that will attach importance
similar the bipheny synthesis when it will work. 3-methylphenol is nitrated to 3-methyl-2,4,6-trinitrophenol and than dissolved in methylene chloride and methanol ratio 1/5, the solution is heated to 50-60 °C, a solution of 5% sodium hypochlorite and 2% NaOH is added to the mix and the dipicric acid is obtained by vaporizing the CH2Cl2/methanol. I don`t know the result contains some remainders of sodium picrate wich have formed ? I guess the way of 3-bromo-2,4,6-trinitrophenol to dipicric acid is more complex. Exuse me that this reply is staying in this topic, it will not meant worse.