Sciencemadness Discussion Board

Salts of Methyl Nitrite

Rhodanide - 11-12-2017 at 06:13

Looking at the Wikipedia page for Methyl Nitrite, it says that "With inorganic basis, it forms explosive salts". Has anyone explored this? Would it be a similar prep to Nitromethanate/Nitronate & Methazonate salts (i.e. reaction of R-NO2 or in this case R-ONO with MOH in alcoholic soln.)? Is it well known knowledge that I just can't seem to find more information on?
This is interesting.
Thanks,
-R/T



(Also, I didn't know that it was explosive. Is iPr Nitrite also this way?)

AJKOER - 12-12-2017 at 04:36

Like with aqueous ammonia (an inorganic base) creating NH4NO2.

The latter is both very toxic and unstable in even aqueous solutions with sudden massive gas formation. The latter explosive qualities is why it is used in blasting in coal mines. It is best created for detonation in situ like by heating together NaNO2 and NH4Cl, as it is not a practical explosive due to excessive sensitivity to shock, even when wet.

[Edited on 12-12-2017 by AJKOER]

Sigmatropic - 12-12-2017 at 14:07

Really AJKOER? "detonation in situ"? It seems like a good description for any energetic accident encountered during chemical synthesis. I can already imagine the experimental: After in situ detonation we recovered some 10% of product, perhaps after 10 more cycles we recover 100%.

Σldritch - 12-12-2017 at 14:23

Methyl Nitrite turns into Nitromethane farly easily i think. It probably just turns to nitronate or something more complex: http://www.sciencemadness.org/talk/viewthread.php?tid=76603

From wiki:
For example, sodium and potassium nitrite reacting with iodomethane would produce mostly nitromethane, with methyl nitrite as the minor product. However, the presence of the silver ion in solution has a stabilizing effect on the formation of carbocation intermediates, increasing the percent yield of methyl nitrite. In either case, some nitromethane and methyl nitrite are both formed.[2]

[Edited on 12-12-2017 by Σldritch]

AJKOER - 12-12-2017 at 19:10

Quote: Originally posted by Sigmatropic  
Really AJKOER? "detonation in situ"? It seems like a good description for any energetic accident encountered during chemical synthesis. I can already imagine the experimental: After in situ detonation we recovered some 10% of product, perhaps after 10 more cycles we recover 100%.


Here is more commentary:

"Heating a mixture of an ammonium salt with a nitrite salt causes a violent explosion on melting, owing to formation and decomposition of ammonium nitrite. Salts of other nitrogenous bases behave similarly. Mixtures of ammonium chloride and sodium nitrite are used as commercial explosives."

Source: http://www.guidechem.com/reference/dic-15333.html

woelen - 13-12-2017 at 02:00

This document is not a very good description of how nitrites behave in practice. There may be a remote chance of unwanted oxidation or ignition, but I've never seen this happen in practice. I have the idea that this document is written by some armchair chemist without any practical backup.

I have done many experiments with nitrites, in aqueous solution, in solid mixes and also in combination with strong solid reductors. I even mixed NaNO2 and red P and ignited that mix. I can tell from experience, that mix can be ignited, but only because of the red P burning in air. The NaNO2 does not react. If I make the same mix with NaNO3 instead of NaNO2, then a very fast whoosh occurs on ignition.

I also made a mix of NH4Cl and NaNO2 and heated that. This mix starts bubbling quite vigorously and becomes wet. The NH4(+) and NO2(-) indeed react, forming N2 gas and H2O. I can imagine explosion of a mix of NH4Cl and NaNO2 if this is heated in a confined container. The N2-gas and water vapor lead to pressure buildup and may lead to explosive rupture of the container. But this also will occur if I heat a mix of NaHCO3 and acetic acid in a closed container.

NaNO2 certainly can be dangerously reactive, it can be a strong oxidizer (but it also acts as a reductor in many situations), but it definitely has no explosive properties with common materials.

NH4NO2 itself is not stable. I once tried to make this salt, by dissolving NH4ClO4 in water and a stoichiometrically equivalent amount of dried KNO2 in some other water and then mixing the two. This leads to nearly quantitative precipitation of KClO4, and NH4NO2 remains in solution at fairly high concentration. I then put this liquid in a warm place in a petri dish, allowing it to evaporate to dryness. After a few days I had nearly nothing left, only a very tiny amount of white stuff (which may be some residual perchlorate salt). Almost all of the NH4NO2 simply had disappeared, apparently it decomposed to N2 and H2O, both escaping/evaporating.

Bert - 13-12-2017 at 15:16



Just on the off chance, I will set a bit of mixed ammonium nitrate/Sodium nitrite in some cheap, expendable and non insulating container over a can of sterno in the middle of a snowy field, light the jellied alcohol and retire.

Arm chair chemist, or armless chemist? Tune in next week...


Rhodanide - 14-12-2017 at 06:47

Quote: Originally posted by Bert  

Arm chair chemist, or armless chemist? Tune in next week...


"In other news, there were reports of a massive explosion in a snowy field late last night,"

Rhodanide - 14-12-2017 at 06:58

Quote: Originally posted by AJKOER  
detonation in situ
[Edited on 12-12-2017 by AJKOER]


*COUGH* Benzenediazonium *COUGH*

A long time ago, on a forum far, far away...

Bert - 14-12-2017 at 11:30
Quote:

Furthermore, my interest in diazonium compounds was piqued by this activity so I did a search on the patent databases. On espacenet, I found a russian patent ( RU2080320 ) which patented the use of 2,4-dinitrobenzenediazonium perchlorate as a low sensitivity, high performance primary explosive. The patent was largely written in russian, so I couldn't understand much of it, but I would think that it could be prepared just like DPNA but from 2,4-dinitroaniline.
For this reason I have been researching a synthetic route to that precursor and have settled on Acetanilide --> 2,4-dinitroacetanilide --> 2,4-dinitroaniline --> DNBDP

AJKOER - 15-12-2017 at 00:14

Apparently, this source notes the use of flameless explosives in coal mines, see https://www.cdc.gov/niosh/mining/userfiles/works/pdfs/acobo.... . The reason cited is coal dust and methane gas presence. So, flameless pressure explosives seem suited as described by Woelen experience with a NH4Cl/NaNO2 mix.
------------------------------------------

From atomistry,com on N2(link: http://nitrogen.atomistry.com/production.html ) to quote:

"Ammonium nitrite, NH4NO2, readily decomposes into nitrogen and water when its solution is gently heated:

NH4NO2 = N2+2H2O.

Actually, in practice, it is found more convenient to warm a solution of sodium nitrite with one of ammonium chloride or sulphate, when the ammonium nitrite, formed by double decomposition, decomposes as above. Overheating should be avoided, otherwise turbulent ebullition occurs."

Another source notes that strong heating of the aqueous mix "can cause the reaction to be explosive" (see https://books.google.com/books?id=1cyWgXMfe6QC&pg=PT73&a...).

With respect to dry NaNO2, a source states "If contaminated by ammonium compounds, spontaneous decomposition can occur" (link: https://pubchem.ncbi.nlm.nih.gov/compound/sodium_nitrite#sec... ).

[Edited on 15-12-2017 by AJKOER]