Snakeforhire
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2,5-dimethoxybenzaldehyde question
Hello all.
I have a 100g flask of this compound that has been stored for the better part of 18 years. It was opened once (by curiosity about the smell it could
have) and then recapped tight and stored away from light, but not from heat (not in the fridge or anything).
Do you guys think it would still be usable in a Henry reaction ?
Any opinions much appreciated 
TY all for reading.
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zed
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Easy enough to find out. Try it.
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Texium
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Thread Moved
16-6-2022 at 06:53 |
Snakeforhire
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Alas, that sadly will have to wait until I manage to source some nitromethane : since february possession of it here is forbidden to individuals as it
is considered an energetic precursor...  
F'ing stupid, as everyone who knows a bit about energetics knows that it's not that easy to make it detonate as is.
So I'll have to see if a professional friend can buy it for me, or maybe register a small company myself. Big PitA...
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mackolol
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Maybe try producing the nitrometane from chloroacetic acid (if you can obtain it), if not the acid can still be made too.
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Rainwater
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A recrystallization with methanol is suggested in this post
http://www.sciencemadness.org/talk/viewthread.php?tid=12667
"You can't do that" - challenge accepted
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Mateo_swe
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Is all forms of nitromethane banned?
Even the methanol/nitromethane racing fuel for model cars and planes?
Here you can buy the nitro RC-fuel if it is lower than a certain %, but they have lowered the %age quite much.
You could distill the nitro RC-fuel to get a methanol/nitromethane mix that is usable in a Henry reaction.
If RC-fuel is not an option you could make it yourself but buying it would be much easier.
If you are inside EU try one of the sellers in the "Reagents and Apparatus Acquisition" section of this forum.
I woluld guess they can provide it for you, maybe even if outside EU.
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clearly_not_atara
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It would still be usable if it is still an aldehyde. That is the only necessary thing about a Henry reaction. In order to determine this, simply form
the bisulfite adduct. This will also allow you to purify it, by removing any fraction which has been oxidized over the years to the benzoic acid.
But if you have no expectation of being able to perform a Henry reaction in the foreseeable future, you might want to think about other things you
could do with it. Obviously, it would not be usable in a Henry reaction if you cannot get any nitro-compounds.
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monolithic
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You could try forming the bisulfite adduct, recrystallize, and then convert back to the aldehyde. I believe this would allow you to separate the main
impurity from oxidation of the aldehyde i.e. the carboxylic acid.
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Snakeforhire
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Quote: Originally posted by Mateo_swe  | Is all forms of nitromethane banned?
Even the methanol/nitromethane racing fuel for model cars and planes?
Here you can buy the nitro RC-fuel if it is lower than a certain %, but they have lowered the %age quite much.
You could distill the nitro RC-fuel to get a methanol/nitromethane mix that is usable in a Henry reaction.
If RC-fuel is not an option you could make it yourself but buying it would be much easier.
If you are inside EU try one of the sellers in the "Reagents and Apparatus Acquisition" section of this forum.
I woluld guess they can provide it for you, maybe even if outside EU. |
Anything that's over 10%. And pre-mixed fuel is pretty expensive.
I'd rather not order from outside the EU if I can avoid it : there'd probably be sniffer dogs at the customs, and they're trained to detect nitro
compounds...
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Snakeforhire
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| Quote: Originally posted by clearly_not_atara | It would still be usable if it is still an aldehyde. That is the only necessary thing about a Henry reaction. In order to determine this, simply form
the bisulfite adduct. This will also allow you to purify it, by removing any fraction which has been oxidized over the years to the benzoic acid.
But if you have no expectation of being able to perform a Henry reaction in the foreseeable future, you might want to think about other things you
could do with it. Obviously, it would not be usable in a Henry reaction if you cannot get any nitro-compounds. |
and, pray tell, what else might I do with it without any nitroalkenes ?
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Snakeforhire
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Well anyhoo, since it seems my choices are limited I guess I'll go the RC fuel route.
One question still lingers in me mind tho : is glacial acetic acid a must for the Henry reaction, or can it be substituted for a less conc. form (80%)
?
[Edited on 18-6-2022 by Snakeforhire]
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PirateDocBrown
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Make a different nitro compound.
Nitroethane is pretty straight forward.
React silver nitrate with sodium nitrite, to get silver nitrite.
Make ethyl iodide with ethanol and iodine.
React silver nitrite and ethyl iodide to get nitroethane.
Victor Meyer reaction.
Doesn't work with methanol, it makes methyl nitrite.
If you want nitro methane in large quantities, you need a tube furnace. Use propane as your carrier gas, and just lead nitric acid vapor in to react
with it. 400 C should do it.
It destroys the propane, and you can condense a mixture of 1- and 2- nitro propane, nitro ethane, and nitro methane out. Frac distill out the compound
you want.
For smaller amounts, reaction of chloro acetic acid and sodium nitrite.
Phlogiston manufacturer/supplier.
For all your phlogiston needs.
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karlos³
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| Quote: Originally posted by Snakeforhire | | Quote: Originally posted by clearly_not_atara | It would still be usable if it is still an aldehyde. That is the only necessary thing about a Henry reaction. In order to determine this, simply form
the bisulfite adduct. This will also allow you to purify it, by removing any fraction which has been oxidized over the years to the benzoic acid.
But if you have no expectation of being able to perform a Henry reaction in the foreseeable future, you might want to think about other things you
could do with it. Obviously, it would not be usable in a Henry reaction if you cannot get any nitro-compounds. |
and, pray tell, what else might I do with it without any nitroalkenes ? |
Have you ever heard about cinnamic acids?
Because they exist.
verrückt und wissenschaftlich
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Snakeforhire
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| Quote: Originally posted by PirateDocBrown | Make a different nitro compound.
Nitroethane is pretty straight forward.
React silver nitrate with sodium nitrite, to get silver nitrite.
Make ethyl iodide with ethanol and iodine.
React silver nitrite and ethyl iodide to get nitroethane.
Victor Meyer reaction.
Doesn't work with methanol, it makes methyl nitrite.
If you want nitro methane in large quantities, you need a tube furnace. Use propane as your carrier gas, and just lead nitric acid vapor in to react
with it. 400 C should do it.
It destroys the propane, and you can condense a mixture of 1- and 2- nitro propane, nitro ethane, and nitro methane out. Frac distill out the compound
you want.
For smaller amounts, reaction of chloro acetic acid and sodium nitrite. |
Thx for the info.
But "semi-industrial" is out of the question for me, way too expensive, no place to do it and overkill for the amount of MeNO2 I need...
And NaNO2 is also restricted here now (only a business can buy it), even though I indeed happen to have some iodine just lying about unused...
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Snakeforhire
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| Quote: Originally posted by karlos³ | | Quote: Originally posted by Snakeforhire | | Quote: Originally posted by clearly_not_atara | It would still be usable if it is still an aldehyde. That is the only necessary thing about a Henry reaction. In order to determine this, simply form
the bisulfite adduct. This will also allow you to purify it, by removing any fraction which has been oxidized over the years to the benzoic acid.
But if you have no expectation of being able to perform a Henry reaction in the foreseeable future, you might want to think about other things you
could do with it. Obviously, it would not be usable in a Henry reaction if you cannot get any nitro-compounds. |
and, pray tell, what else might I do with it without any nitroalkenes ? |
Have you ever heard about cinnamic acids?
Because they exist. |
Sure. But AFAIK their chemistry requires acetic anhydride, which is about as hard to get as virgin ass in TJ... 
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Snakeforhire
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Anyway, thx for all your replies. Topic can be consired closed now AFAIC
I'll think about all that for a long, long time before deciding on doing anything.
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clearly_not_atara
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Attachment: henze1940.pdf (408kB)
This file has been downloaded 223 times
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PirateDocBrown
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| Quote: Originally posted by Snakeforhire |
And NaNO2 is also restricted here now (only a business can buy it), even though I indeed happen to have some iodine just lying about unused... |
Extract it from Prague powder pink curing salt. The #1 type is about 6% NaNO2.
Phlogiston manufacturer/supplier.
For all your phlogiston needs.
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Snakeforhire
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Nah, too expensive and tedious.
I'll just ask a friend who has a business to order it for me when I see him. It's nothing suspicious so he wouldn't risk anything.
Anyway, nitroethane isn't the priority. First I needs to distill me some RC fuel. 
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