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Author: Subject: DDNP & related compounds: The über thread!
Rosco Bodine
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[*] posted on 5-3-2018 at 17:23


@nitro-genes

That is your work nitro-genes so no need to credit me as a co-author of your work, when all I did was help with some references and added some untested ideas of my own. So you rightly own the copper[+1] cuprous / ascorbic acid reduction scheme. Let me own the magnesium idea... glycine ...ect. especially if all that turns out to be a "seemed like a good idea" that doesn't work at all. I'm good at thinking ideas that work great on paper and in theory but don't always work so great in the flask put at risk, when the laboratory and lab personnel are still around to report the interesting results ;)
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[*] posted on 6-3-2018 at 11:32


You were the first to recognize the product as picramic acid and provided references that pointed towards the yellow-greenish compound likely to be copper picramate and also its solubility in HCl.

The magnesium and glycine idea may be worth pursueing, in the ideal scenario glycine complexation may keep the copper picramate soluble indeed and allow the use of catalytic amounts of copper, without precipitating any magnesium picrate (like for sodium) during the reaction at near neutral or slightly acidic pH.

As said before though, doing these reactions is very time and material consuming and there are many other experiments I would like to do with picric acid, the copper/ascorbic reduction being mostly figured out.
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[*] posted on 6-3-2018 at 15:20


Yeah I think because of the complex parallel reaction pathways that are possible that is a similar story with the Zinin reduction scheme, it is definitely possible to tweak the reaction to obtain higher yields. Hennig was doing some sorting out of the variables for the Zinin reduction and got the yields to go up from around 80% in the beginning to later in the 95% to 100% by what are really trivial changes to the basic process. Very probably it is possible to refine the process if it follows the same for alternative schemes to the Zinin. These reduction schemes are somewhat general and what works out good for one reduction may also work well for other reductions as is or with slight adjustments.

This is probably novel what you have reported for the ascorbic acid and copper sulfate used to produce picramic acid. So all the Google searches on this topic will and already do lead here to SM. There is quite an extensive little compendium of obscure articles and experiments here at SM that is nowhere else to be found.

I am thinking about the diazotization and the scheme you described using copper wire.
If the picramic acid is dissolved in nitric acid strong enough to form the picramic acid nitrate via the amphoteric property similarly as was observed for the isopicramic acid, and copper wires are added, then the byproduct NO2 should work similarly as occurred when you were preparing the iso-DDNP or p-DDNP by diazotizing isopicramic acid nitrate. By using a 50/50 mixture of the picramic acid and isopicramic acid it may be possible to produce a racemic co-crystallized mixed isomer DDNP having unique properties and crystalline form if such a mixed isomer does exist and can be formed.

With regards to an alternative candidate transition metal salt that could function in small quantity as a regenerable catalyst not being sequestered as picramate during the reduction any of the ones described by Girard in 1853 may work as well as does the copper for the actual reduction, but by remaining in solution can be regenerated. For example, nickel sulfate, or possibly better nickel acetate or other organic acid nickel salt, is a candidate.

And these reduction schemes may likewise be applicable to styphnic acid for reduction to styphnamic acid for diazotization to DDNR.

soluble picramates not precipitated Girard Comptes Rendus 1853.bmp - 192kB



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[Edited on 3/7/2018 by Rosco Bodine]
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[*] posted on 7-3-2018 at 15:44


Of all transition metals, copper seems to have the highest catalyzing effect on the reaction of ascorbic with oxidizers (see figure 5 in particular)

The Influence of Transition Metal Ions on the Kinetics
of Ascorbic Acid Oxidation by Methylene Blue in
Strongly Acidic Media

https://pdfs.semanticscholar.org/842b/11206b5630a7ba354d4727...

Iron comes in second, so I tried the reduction of picric to picramic using Fe(II)sulfate/ascorbic today:

Eperimental:

0.5 g of picric were added to a 20 ml beaker together with 15 ml water and brought to 60 C. The pH was adjusted to 7 using NaOH solution. Then 1.75 grams of ascorbic were measured out and added at once. About 200 mg of ferrous sulfate was added, which resulted in no color change or exotherm within 10 minutes. The pH was increased by dropwise additions of 5% household ammonia. Each added drop produced a dark black solution, which reverted to a clear orange after few seconds. With each drop of ammonia, the solution did became a noticably darker shade of red in colour. After a pH of near neutral was reached, the solution was a inmensely dark red in colour and gas formation became noticable. A sharp exotherm caused a rapid increase in temperature to 80 C, with pronounced foaming. The end result was an incredibly dark red solution (light could hardly pass through it, even though the solution was completely clear) Adding acetic acid to a pH of 3 precipitated some dark brown amorpous stuff.

So it seems iron can catalyze the reduction, though no picramic was produced at all. maybe the dark colour was from a nitro-diamino-phenol from over reduction or the partial recution produces reacted with ascorbic or any of its decomposition products. Why copper(I) seems much more specific is interesting.
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Rosco Bodine
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[*] posted on 7-3-2018 at 16:30


I believe picramic acid is absolutely being produced even without the ascorbic acid to assist but conditions for the isolation and identification of the product are not right. I'll get back with more on this later.

Over in the other thread I was reviewing this post
http://www.sciencemadness.org/talk/viewthread.php?tid=433&am...

[Edited on 3/8/2018 by Rosco Bodine]
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[*] posted on 7-3-2018 at 17:20


There is no way iron will work in high yield using ascorbic or using Fe(0). The Fe(II)(hydr)oxide method you are refering to produces only very small amounts of picramic and very dark red solutions, likely indication aspecific reduction, as was also briefly mentioned in the french article you posted a while back. None of these methods mention yield, except for the Fe(0)/NaCl/water method posted by Axt, which claimed something like 98% yield, I don't buy it...Noone would be using sulfide reductions if this was the case.

From my experiment, sodium picrate in the presence of ascorbic acid and Fe(II) also does not result in any reduction, which is not surprising since it was already knwon that boiling ferrous sulfate with sodium picrate does not result in any reduction. It seems, adding ammonia dropwise to the picrate/ascorbic/Fe(II) solution was a best guess possible way to use ascorbic acid with fe(II) catalysis and it didn't work. No picramic was formed and I don't see it working otherwise. Interesting why the copper works so well. It would be an interesting test to see whether some soluble cuprous salt in a weak acid (something like cuprous acetate/acetic acid) would be able to reduce sodium picrate...

[Edited on 8-3-2018 by nitro-genes]
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Rosco Bodine
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[*] posted on 7-3-2018 at 18:22


That article posted by Axt was published as a contribution from an American laboratory at the University of Chicago in what was the premier chemistry professional journal of the era. It was in that same Chicago laboratory was built the world's first nuclear reactor.
The level of peer review for that article published 90+ years ago would very likely have been extreme and exhaustively thorough.

Berichte der deutschen chemischen Gesellschaft

http://onlinelibrary.wiley.com/wol1/doi/10.1002/cber.1927060...

Robert Edward Lyons, Ph.D. had been a Ph.D. and head of the university chemistry department for more than 30 years when that article was published.

http://webapp1.dlib.indiana.edu/archivesphotos/results/item....

In this post nearly four years ago I had done more study about the ferrous sulfate reduction

http://www.sciencemadness.org/talk/viewthread.php?tid=433&am...

You are encountering conflict with lowering the pH for using ascorbic acid instead of an ascorbate salt and I think also the order or manner of addition or both could be a factor.

I'll think more about the process and what may help.

"dark red solutions" standing in the cold sometimes produce some crystals of a picramate salt in good time :D

Your "dark brown amorphous stuff" is likely picramic acid but the color is off due to the state of subdivision and probable impurity of iron.

If you check the amorphous stuff will probably redissolve in HCl to form the picramic acid hydrochloride and on dilution will likely precipitate something looking more familiar.

I think you are making some overly broad general conclusions that aren't necessarily governing because of a very specific scenario where you see the unexpected occur. Hang in there and sort it out.

Process chemistry is highly nuanced and what may seem to be insignificant small changes can produce a drastic change in the course of a reaction and the resultant yield. There are an assortment of reactions where a small change in temperature or pH or the sequence and rate of addition or the form in which the reactants are brought into contact and intermixed, solubilities and concentrations also can all have enormous bearing ....and this reduction is definitely one of those more "fickle" reactions, evident from reading the earliest articles and later articles too. So, what on first glance appears at first may not work, may later work even splendidly well when the precise conditions needed are determined and provided. Calibrating the process conditions involves applied algebra that can't really be derived from one experiment. When you describe a dark red to almost black solution along with the exotherm, that is a good indicator of reduction to sodium picramate which is a very strong dye and would remain dissolved in super saturated solution in the hot alkaline liquid, but should crystallize out in the cold and on standing.

Something that could be occurring that makes the copper attractive and useful relates more to the insolubility of the copper picramate than to any catalytic activity with ascorbic acid. The reduction may be enhanced by being solubility driven due to the product precipitating as fast as it forms. That theory would be proven by use of other reducing agents than ascorbic acid in the presence of copper as a "solubility reagent" where basically the product is appearing like a low solubility "spot test" result. The "complex" with copper may have nothing to do with ascorbic acid, but could be a mixed valence copper salt, a double salt of cuprous picramate / cupric picramate. Only analysis of the intermediate precipitate would tell more or tell conclusively what is occurring. With simultaneous multiple different reaction paths possible, there could be an indefinite mixture of products of sodium picramate, cupric picramate, and cuprous picramate ....all present as possible mixed "picramate values" and likewise for other reductions using other metal salts as reagents or catalysts.

[Edited on 3/8/2018 by Rosco Bodine]
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[*] posted on 9-3-2018 at 15:31


On heating picric to its ignition point, there is a definite sign of reduction going on, maybe picramic can be isolated from the condensed vapours. :D

Granted, you have a point about my conclusion about the iron reduction never to reach high yield being premature. Noticed in the article they used iron from which all organic contaminants were removed by glowing out (85% iron) maybe the oxydes introduced could be a factor. Still, I have a really hard time believing the 100% yield mentioned, hardly any information on isolation and compound identification is present, except mention of sodium carbonate extraction. As an amateur this may be acceptable to a certain extent, especially when on closer look, no definite conclusions are generally made at all. ;)

The mixed valence picramate theory is interesting, but with such an excess of ascorbic acid and the very fast conversion of Cu(II) to Cu(I) (Even in the cold) I find it very hard to believe as well. A sodium double salt might also be possible, that is why I wrote "perhaps" in the report IIRC. Looking at the properties of Cu(I) salts and there ease of hydrolysis in general, it seems strange so little copper(I)oxide is isolated under these weakly acid conditions. Maybe most of the copper(I) remains as a Cu(I)ascorbyl radical complex during the reaction?

You mentioned at least 4 reactions to be possible during the copper/ascorbic reduction of picric, could you shed some more light on your thinking on this matter?

[Edited on 9-3-2018 by nitro-genes]
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[*] posted on 9-3-2018 at 18:34


Quote: Originally posted by nitro-genes  
On heating picric to its ignition point, there is a definite sign of reduction going on, maybe picramic can be isolated from the condensed vapours. :D

One ferrous picrate reduces another ferrous picrate to ferrous picramate just like one hand washing another. Didn't you get the memo that went out about 90 years ago? :P Sheesh...My dear missus, do hand me a new spoon feeding spoon since this one I have been using is worn down to the nub. And fetch for me my German - English dictionary and reading glasses. :P:D Seriously the end product is probably ferric picramate since likely the ferrous picramate is active as a reducing salt also, and there is a 6H+ represented by the 3:1 molar ratio of elemental Fe(++) to picric acid described by Lyons and Smith.
Quote:

Granted, you have a point about my conclusion about the iron reduction never to reach high yield being premature. Noticed in the article they used iron from which all organic contaminants were removed by glowing out (85% iron) maybe the oxydes introduced could be a factor. Still, I have a really hard time believing the 100% yield mentioned, hardly any information on isolation and compound identification is present, except mention of sodium carbonate extraction. As an amateur this may be acceptable to a certain extent, especially when on closer look, no definite conclusions are generally made at all. ;)

You have me at a disadvantage because my German is awful.
Sponge iron or water jet cut powder iron would probably do better than 80 mesh iron filings.

This form of iron is what I was thinking should work well.

https://www.ebay.com/itm/Hoeganaes-Ancor-MH-100-Sponge-Iron-...

I still think zinc or aluminum amalgam would work fine. Aluminum amalgam or zinc amalgam is piss easy.

Quote:

The mixed valence picramate theory is interesting, but with such an excess of ascorbic acid and the very fast conversion of Cu(II) to Cu(I) (Even in the cold) I find it very hard to believe as well. A sodium double salt might also be possible, that is why I wrote "perhaps" in the report IIRC. Looking at the properties of Cu(I) salts and there ease of hydrolysis in general, it seems strange so little copper(I)oxide is isolated under these weakly acid conditions. Maybe most of the copper(I) remains as a Cu(I)ascorbyl radical complex during the reaction?

The ascorbyl or dehydroascorbyl could have a chelating effect but I doubt it is the predominating influence on the copper.

When future experiments are done if you are sticking with sodium as the alkali maybe half-neutralize the ascorbic acid solution to a 50/50 molar ascorbic / sodium ascorbate. But magnesium would work better :D Reference the Clayton article and discussion about pH control that Hennig and I were sorting out with regards to the different reduction yields being pH sensitive, (in the other thread).

Picramate is a devil about pH sensitivity affecting yields, also temperature and reaction mixture concentration are other tricksters.

Regarding the possible formation of a mixed valence copper picramate double salt:

There is cupric picrate present in solution before the ascorbic acid is added and it is possible for that to be reduced to cupric picramate ...if there is not a specifically selective reduction of the cupric to cuprous in preference to reduction of the picrate to picramate.

Of course if the reduction went to completion all that would be present in the end would be entirely cuprous picramate. However, if there was formed a mixture of partly reduced and fully reduced copper picramates that tended to form an insoluble double salt there could be a mixed valence double copper picramate that accounts for the insoluble product chemical composition showing a discrepancy on analysis from what should be the mole weight and analysis for cuprous picramate.

It is uncertain what is the selectivity for the species being preferentially or first acted upon by the ascorbic acid .......is it the copper being first reduced, or is it the picrate, or is it a mixture of both reactions? You see the uncertainty present in a chaotic system allows for several different reductions and subsequent reactions for the reduced copper in particular, since its oxidation state can change. Reduced copper associated with either picrate or picramate can operate as a reducing agent itself towards unreduced picrate.

Quote:

You mentioned at least 4 reactions to be possible during the copper/ascorbic reduction of picric, could you shed some more light on your thinking on this matter?

[Edited on 9-3-2018 by nitro-genes]


There is possibly a couple more that are pH and hydrolysis dependent

Reduction by ascorbic H++ (free ascorbic at < 4 pH)

Reduction by mono-dehydroascorbic H+
(cuprous ascorbate or sodium ascorbate)

Reduction by cuprous picrate (reduction by the Cu+1)

Reduction by cuprous picramate (reduction by the Cu +1)

Ascorbate will by itself reduce Picrate to Picramate

https://www.jstage.jst.go.jp/article/bcsj/65/4/65_4_1101/_ar...

Put on your thinking cap, and think about the concept of a regenerable catalyst needing to remain in solution, because copper won't do it. Obviously copper is useful for isolation because of the insoluble precipitate it does form. But that same usefulness works counter to the concept of a regenerable catalyst, because once the copper combines with the product it is sequestered by precipitation and leaves the reduction reaction, like a player in a sports game that has scored and as a reward has been benched....that copper is no longer participating in the reduction reaction and has been consumed and locked away in the insoluble precipitate. So then for a regenerable catalyst, a better candidate would be a metal that easily changes oxidation states either direction, but behaves differently and does not form an insoluble precipitate with either the picric or picramic value, but remains in solution to be recycled and regenerated as an intermediate reducing agent so that more usefulness as a catalyst is realized. Of course there would need also to be no precipitation of the catalyst due to reaction with the Ascorbic Acid or Ascorbate Salt, and no other reduction reaction parameter such as pH that would provoke precipitation of the soluble catalyst.

So what transition metal salts would be likely catalyst candidates?

Manganese, iron, cobalt, and nickel are likely and each would probably be optimal at a particular pH, temperature, and concentration which would need to be "process engineered" by the chemist / technician /operator keeping that pH and other parameters in mind with regards to order and time of addition and the reagents used.

My intuition about these was first on Manganese due to good solubility of the picrate and picramate, but what is the sensitivity with Ascorbic or Ascorbate is unknown. Nickel was another thought because of similar chemistry with copper but no report of an insoluble picramate to complicate things.

My collateral thoughts about buffering using Magnesium as the base was likewise good solubility for the picrate and picramate and having a limited swing for pH inherent by use of Magnesium for the base. Likewise using organic acid salts instead of mineral acid salts would dampen pH swings. And my thoughts regarding glycine as potentially useful related to a twofold potential usefulness as an organic acid buffer and solubility enhancer via chelation as well as a solubility enhancer for picric acid in a low pH reduction system which would enhance the activity of Ascorbic acid at a lower and optimum pH of about 2-3 pH where free Ascorbic acid is at peak activity as a 2H (++) value reducing agent.

soluble picramates not precipitated Girard Comptes Rendus 1853.bmp - 192kB

As a further thought, some reactions absolutely do run differently on infusion of reactant streams by a Sigma pump flow through a capillary into a rapidly stirred reaction mixture as a finessed very gradual addition, rather than addition by "bucketful" splashes of drips for addition, or where the reactants are simply dumped together "in a lump" and a mass reaction follows where the process on a molecular level is like a bar room brawl :D

It depends on the target material being made what addition scheme may work better and there can be quite a difference in yield for some of the reactions, and even some reactions that can only be done by infusion to produce good results. I don't think this reduction is all that sensitive, but some of the diazotizations for example like for nitrotetrazole are indeed that sensitive.

When you devised that diazotization scheme using copper wire as a source for NO2 gas evolution that essentially emulated a Sigma pumped infusion diazotization scheme in situ, and is a lot simpler and more economical than using a Sigma infusion pump to very slowly inject a micro stream of nitrite solution into the reaction mixture. That thinking cap is the one I was referencing.


[Edited on 3/10/2018 by Rosco Bodine]
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[*] posted on 14-3-2018 at 19:44


Quote: Originally posted by Rosco Bodine  
Diazodinitrophenol - as a free running crystalline powder from a nitric acid diazotisation

Abstract:

Diazoltisation of picramic acid to produce the explosive is effected in nitric acid in the absence of hydrochloric or sulphuric acids or their salts and pref with as low a sodium content as possible. Conventional products tend to adhere to surfaces.

A translation of the attached patent FR2106904 may be useful



Attachment: Machine Translation English FR2106904A5 Diazodinitrophenol.pdf (18kB)
This file has been downloaded 73 times

Calcium nitrite could be an alternative means of diazotization to eliminate the sodium ion, if the calcium ion is not responsible also for lowering the quality of crystals of DDNP similarly as the sodium ion. It would be easier to lower the concentration of calcium ion in a residual solution of nitrous acid by use of an acid that would precipitate most of the calcium as an insoluble byproduct, sulfuric, phosphoric, oxalic, ect.

Calcium nitrite would also be easily converted to other nitrites by double decomposition reactions with carbonates or sulfates, ect. that would precipitate the insoluble calcium salt and leave a solution of the desired different nitrite product.

An additional scheme for diazotization of picramic acid might employ an organic nitrite such as ethylene glycol nitrite or perhaps glycerol nitrite used as the nitrosation reagent.

A gaseous nitrosation reagent such as methyl nitrite introduced through a dispersion tube into a picramic acid solution may also be workable.

Attachment: US4294813 Calcium Nitrite from Sodium Nitrite.pdf (103kB)
This file has been downloaded 56 times


Attachment: blinded.mid (27kB)
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[Edited on 3/15/2018 by Rosco Bodine]
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[*] posted on 21-3-2018 at 13:05


Regarding the Cu(II)/ascorbic reduction of picric to picramic:

Would nano-copper itself be able to reduce picric? Or would this be a side reaction causing yield reduction instead. Noticed some mention of aminoacid additions to control for smaller copper particle sizes from chemical reduction methods, is this what you had in mind with the glycine additions Rosco? Not sure if the nano copper would be able to react easily again with copper(II)sulfate to form transient copper(I)sulfate. Would chloride content also be a factor for this? From the second article attached it seems this might be the case, even in abscence of HCl.

Tried making some nano-copper from ascorbic reduction of copper(II)sulfate in water and boiling for an hour a few days ago. I somewhat doubt this produces actual nano copper though, as the particle size appears larger instead (difficult to say though due to potential agglomerations formed). The attached artcle mentions nano copper is produced best from dilute solutions at close to neutral pH and temperatures between 60-80 C. They also mention the ascorbic to acts as a capping agent to keep the particles in suspension, though no supporting evidence for this is presented in the entire paper, which would have been interesting to read. This might explain however the low 50% yield of copper powder from Cu(II) reduction by ascorbic, even in the presence of a large excess of ascorbic. Only the larger copper particles (or agglomerates of nano-powder) are filtered off, leaving a lot of the nano-copper in suspension.

Attachment: Experimental Investigation on the synthesis of copper nanoparticles by chemical reduction method - Copy.pdf (1.1MB)
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[Edited on 21-3-2018 by nitro-genes]

Attachment: Representation of the Solubility of CuCl in Solutions of Various Aqueous Chlorides - Copy.pdf (725kB)
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Rosco Bodine
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[*] posted on 21-3-2018 at 20:51


Colloidal copper might be active as a reducer ....I'm not sure. Glycine would probably be helpful there as a sort of "emulsifier" or stabilizer that would operate as a solubilizer / chelating agent ....which essentially "associates" metal and organic acid as a sort of loose covalent / quasi ionic "salt" but not exactly a stable "electrical" salt like a usual mineral salt would be. The charge there for the compound association is minimal to almost non-existent. A chelate is almost like a soap or detergent "wetting agent" like a very minimal "glue" on a "sticky note" attachment of two things.

The "male" metal and "female" organic acid of a chelate are not joined in a tightly bonded "super glued" attachment, but are associated like "friends with benefits" :D not involved in some deeply committed soul mate sort of bonded relationship. :D

The organic acid offers mister macho metal a little joyous cathode stimulation / R&R / rejuvenation for the afternoon or as long as it can last ...until assertive competition arrives and it is time for girlfriend to go :D

My idea for using the glycine is raising the upper limit pH and soluble metal concentration where a metal hydroxide would precipitate, making the reaction less sensitive to alkalinity. It was also a means of working with an organic acid salt of the metal in a system that would have inherent buffering not present to as great an extent with mineral acid salts. Glycine would help tame the pH swings and the pH gradient in the reaction mixture where additions are being made dropwise also, because each added drop has a local reaction condition that fades across a gradient until the added drop of reactant becomes mixed thoroughly well with the bulk of the material being stirred in a beaker.

Adding a reactant solution dropwise is like dripping a red paint into a stirred bucket of white paint, and across the swirl of mixing different materials is a million different shades of pink before long stirring makes the entire bucketful an even color pink. In a chemical reaction a buffer helps narrow the range of extremes of pH that can occur only across a smaller limited gradient of pH for the mixing solutions.

The use of glycine in another scheme was as a solubility enhancer for picric acid that might be reducible to picramic acid or a picramate, particularly the magnesium salt. I tried to give a detailed and coherent description earlier what were my thoughts on that. My focus and note on magnesium having potential usefulness is explained more in this linked post in another thread.

http://www.sciencemadness.org/talk/viewthread.php?tid=433&am...

Note to moderator:

There needs to be an editing / export / merge done for the DDNP and picramic acid topic specific posts that have mislocated the discussion in another thread making it impossible to keep track of the discussion.

See the enumerated 23 posts below need to be merged following this linked post in this thread

(1-12-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=439&am...

That merge should fill the chronological gap in this thread where the off topic posts are located in a different general topic.

Nitro-genes started this detour off topic by not recognizing the subject matter for the unknown compound he had made. So this (linked below) first post "detour" off topic should be merged into this thread and all the posts listed should be exported to this topic thread, DDNP & related compounds: The uber thread!

[1] (1-14-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[2] (1-15-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[3] (1-15-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[4] (1-15-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[5] (1-16-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[6] (1-16-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[7] (1-16-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[8] (1-17-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[9] (1-17-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[10] (1-17-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[11] (1-17-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[12] (1-17-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[13] (1-17-2018) Rosco Bodine

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[14] (1-23-2018) nitro-genes)

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[15] (1-23-2018) Rosco Bodine

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[16] (1-23-2018) nitro-genes

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[17] (1-24-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[18] (1-24-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[19] (1-24-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[20] (1-26-2018) nitro-genes

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[21] (1-26-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[22] (1-27-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

[23] (1-30-2018) Rosco Bodine

http://www.sciencemadness.org/talk/viewthread.php?tid=26572&...

Additional note to moderator:
There may need to later created a 3 branched bracketed grouping of this topic thread with the picramic acid from picric topic thread and the Picric acid: different instructions topic thread since the three topics are an inherently related "trifecta" sort of overlapping discussion. That would help organize the three related topics.

[Edited on 3/22/2018 by Rosco Bodine]
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nitro-genes
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[*] posted on 26-3-2018 at 11:32


Would be interesting to know how exactly the reduction is occuring. Would something like this (Copper phthalocyanine-3,4′,4″,4″′-tetrasulfonic acid) be "glueye" enough to allow for catalysis? Or would the ascorbic still reduce the copper right back to the metal? It would be somewhat sterically hindered though. :P

https://www.chemicalbook.com/ProductChemicalPropertiesCB6113...

[Edited on 26-3-2018 by nitro-genes]
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