Sciencemadness Discussion Board

Acetonitrile uses

Rhodanide - 8-12-2017 at 06:17

Hi everyone. I have a good amount of Acetonitrile (500mL), and don't really know what to do with it. Are there any interesting reactions which I can do with it, or complexes which can be made? I know it burns with a pinkish flame, but I don't really want to waste it that way. Thoughts or suggestions? I couldn't really find much online about this.
Thanks,
-R/T

Chemvironment - 8-12-2017 at 07:13

If I recall correctly some college buddies were using it for DNA synthesis or peptide sequences or something of that nature. Idk if that floats your boat.

DraconicAcid - 8-12-2017 at 08:21

I seem to recall that it coordinated to copper(I) quite well, and that copper(I) is the stable form of copper in acetonitrile solution.

Rhodanide - 8-12-2017 at 08:55

Quote: Originally posted by Chemvironment  
If I recall correctly some college buddies were using it for DNA synthesis or peptide sequences or something of that nature. Idk if that floats your boat.


That's.. interesting, but it sounds more like biochemistry as opposed to inorganic, simple organic and organometallic chemistry, which is my interest area.

Sigmatropic - 8-12-2017 at 09:45

Among other things It can be used to make acetyl chloride and hence acetic anhydride.

clearly_not_atara - 8-12-2017 at 13:32

It is a good solvent for the preparation of organozinc reagents from allyl, benzyl, and aryl halides (usually bromides), the latter using a cobalt (I) catalyst generated in situ. See e.g.:

Allyl and benzyl halides:
https://www.thieme-connect.com/products/ejournals/html/10.10...
https://www.thevespiary.org/rhodium/Rhodium/Vespiary/talk/fi...
http://www.journal.csj.jp/doi/pdf/10.1246/cl.1981.1135 (slightly inferior to glyme in this case, 73% vs 83% yield)

Aryl halides:
http://onlinelibrary.wiley.com/doi/10.1002/chem.200204604/fu...
https://s3.amazonaws.com/academia.edu.documents/44508014/Che...
http://www.sciencedirect.com/science/article/pii/S0040403903...
http://www.sciencedirect.com/science/article/pii/S0040403905...

The arylzinc reagents can be transmetallated to arylcopper reagents as long as the arene is not electron-deficient, in which case a biaryl formation is observed; Le Gall et al 2005, attached. Presumptive dimerization mechanism: Ar-CuX + Ar'-ZnX >> ZnX2 + Cu + Ar-Ar'

[Edited on 8-12-2017 by clearly_not_atara]

Attachment: legall2005.pdf (99kB)
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Melgar - 8-12-2017 at 16:04

It can be reacted with Grignard reagents to produce methyl ketones on hydrolysis.

Rhodanide - 11-12-2017 at 05:54

These are great and all, but all the complicated organic chem experiments are out of my reach...

Chemvironment - 11-12-2017 at 06:56

Its a polar aprotic solvent like dmf, acetone, or dmso. Just use it as such.

Rhodanide - 11-12-2017 at 08:14

Quote: Originally posted by Chemvironment  
Its a polar aprotic solvent like dmf, acetone, or dmso. Just use it as such.


Ok, great.

Nicodem - 11-12-2017 at 13:52

Old topic, already discussed:
https://www.sciencemadness.org/whisper/viewthread.php?tid=13...

It helps using the forum search engine before opening new topics.

woelen - 11-12-2017 at 13:53

It can be used as a solvent for making strongly fluorescent ruthenium complexes. I did some experiments with Ru-bipyridine complexes, dissolved in CH3CN. With addition of some Mg-filings and dilute HCl you get amazing very bright orange fluorescence.

So, if you have ruthenium and bipyridine, then acetonitrile is a very interesting solvent.

Rhodanide - 13-12-2017 at 05:55

Quote: Originally posted by Nicodem  
Old topic, already discussed:
https://www.sciencemadness.org/whisper/viewthread.php?tid=13...

It helps using the forum search engine before opening new topics.


I saw that thread already, but it didn't answer my questions. The thread was mostly filled with people pondering how to dry Acetonitrile, and maybe one or two threads which actually discussed uses. I did see your post about the Epoxidation of Alkenes, which interests me. I have a brand new bottle of 35% H2O2, so maybe I'll give that a try. I just need to find an Alkene lying around... (suggestions?) Can it Epoxidize organics like soybean oil?

BromicAcid - 13-12-2017 at 18:26

Quote: Originally posted by Tetra  
I have a brand new bottle of 35% H2O2


Quite a rare find indeed ;)

I procured acetonitrile sometime back to make trimethylsilyl nitrate from trimethylsilyl chloride and silver nitrate dissolved in acetonitrile, the silver chloride crashes out. It was a literature prep that went exactly as planned.

[Edited on 12/14/2017 by BromicAcid]

Perchlorate - 13-12-2017 at 23:11

I managed to find a 4L bottle of HPLC-grade Acetonitrile (For the equivalent of 27 US dollars), so I have a similar problem now... :D

Some uses include Chemplayer's Acetyl Chloride: https://www.youtube.com/watch?v=Q2ArDw0vf2Q
Production of [Cu(CH3CN)4]+ : sorry, couln't find a good preparation...

Of course, Acetonitrile can be used as a solvent for a bunch of reactions, but the most interesting for me are probably:

Fluorination of Pyridines and Diazines with AgF2 in Acetonitrile :http://www.orgsyn.org/Content/pdfs/procedures/v94p0046.pdf
Preparation of Sulfonyl Chlorides via N-Chlorosuccinimide in Acetonitrile; http://www.orgsyn.org/Content/pdfs/procedures/v91p0116.pdf

DraconicAcid - 13-12-2017 at 23:23

Quote: Originally posted by Perchlorate  
Production of [Cu(CH3CN)4]+ : sorry, couln't find a good preparation...

Dissolve any anhydrous copper(II) salt in acetonitrile, and stir over clean copper wire or shavings.

Rhodanide - 14-12-2017 at 06:42

Quote: Originally posted by Perchlorate  
I managed to find a 4L bottle of HPLC-grade Acetonitrile (For the equivalent of 27 US dollars), so I have a similar problem now... :D

Some uses include Chemplayer's Acetyl Chloride: https://www.youtube.com/watch?v=Q2ArDw0vf2Q
Production of [Cu(CH3CN)4]+ : sorry, couln't find a good preparation...

Of course, Acetonitrile can be used as a solvent for a bunch of reactions, but the most interesting for me are probably:

Fluorination of Pyridines and Diazines with AgF2 in Acetonitrile :http://www.orgsyn.org/Content/pdfs/procedures/v94p0046.pdf
Preparation of Sulfonyl Chlorides via N-Chlorosuccinimide in Acetonitrile; http://www.orgsyn.org/Content/pdfs/procedures/v91p0116.pdf


Dear god man, now you've got enough VOCs to knock out a herd of elephants! If I'm correct, HPLC is the purest you can get, right? What an incredible find, 4L for $27. Now just go win the lottery!

zed - 18-12-2017 at 15:37

Keep in mind, there are occasionally toxicity problems with Acetonitrile. Historically, it was used industrially in "sealed" systems. When it entered the realm of more common chemical lab usage, some deaths were precipitated.

Handle with caution. Treat with respect.

Seems like hydrolysis could take place in several ways. Acetonitrile+ H2O > Acetic Acid + Ammonia Or Acetonitrile + H2O > Ethanol + HCN. Depending on where you are, on the "Bell Curve", problems could arise.

Folks sometimes slosh the stuff around, get it all over themselves, then go home, go to sleep...... and never wake up again. Seems like Nail Salons, lost a few beauticians that way.

Rhodanide - 19-12-2017 at 06:21

Quote: Originally posted by zed  
Keep in mind, there are occasionally toxicity problems with Acetonitrile. Historically, it was used industrially in "sealed" systems. When it entered the realm of more common chemical lab usage, some deaths were precipitated.

Handle with caution. Treat with respect.

Seems like hydrolysis could take place in several ways. Acetonitrile+ H2O > Acetic Acid + Ammonia Or Acetonitrile + H2O > Ethanol + HCN. Depending on where you are, on the "Bell Curve", problems could arise.

Folks sometimes slosh the stuff around, get it all over themselves, then go home, go to sleep...... and never wake up again. Seems like Nail Salons, lost a few beauticians that way.


I just think it's fascinating how most nitriles are around 30-90mg/kg for the LD50, while Acetonitrile is somewhere in the range of over 2,400mg/kg. It's still toxic though, and still a Nitrile, so there's that hazard.

If it's around as toxic as Toluene or similar solvents, then I should have nothing to worry about.

Metacelsus - 19-12-2017 at 07:28

Quote: Originally posted by zed  
Or Acetonitrile + H2O > Ethanol + HCN. Depending on where you are, on the "Bell Curve", problems could arise.


It would be methanol + HCN, since acetonitrile is CH3CN.

Also, for that organozinc reaction mentioned by clearly_not_atara, I'm surprised the organozinc reagent doesn't react with the acetonitrile to form an imine (which would be the analogous reaction for a Grignard organomagnesium). Maybe it's just that the aldehyde (or imine formed in situ by reaction of the aldehyde and an amine) reacts more quickly and consumes all the organozinc before it has a chance to react with the acetonitrile.

[Edited on 12-19-2017 by Metacelsus]

clearly_not_atara - 19-12-2017 at 09:18

There is a reaction between organozinc reagents and nitriles but it requires a reflux:

http://www.organic-chemistry.org/namedreactions/blaise-react...

Aldehyde addition occurs at rt or lower. Imines and acyl halides/anhydrides also work. Weinreb amides and thioesters have not been tried IIRC. Ketones are apparently unreactive because someone would definitely have tried. Isocyanates might also react... if you're for some reason disappointed that the rxn isn't dangerous enough.

I really don't see why the rxn is above anyone's head, it's much easier than a Grignard from all the reports I've read.

JJay - 19-12-2017 at 10:41

That's interesting... Grignards are more stable when exposed to air than organozinc reagents... does the Blaise reaction require an inert atmosphere?

DraconicAcid - 19-12-2017 at 12:09

Quote: Originally posted by zed  
Seems like hydrolysis could take place in several ways. Acetonitrile+ H2O > Acetic Acid + Ammonia Or Acetonitrile + H2O > (m)Ethanol + HCN.


Wait, are you suggesting an Sn2 reaction in which cyanide is the leaving group? I glare at you skeptically, because cyanide is a crappy leaving group, and the triple-bonded carbon is much more susceptible to attack than the methyl one.

clearly_not_atara - 19-12-2017 at 14:50

Quote: Originally posted by JJay  
That's interesting... Grignards are more stable when exposed to air than organozinc reagents...
Where did you hear this? Some organozincs are air-stable period:

http://onlinelibrary.wiley.com/doi/10.1002/chem.201403015/fu...

Are you comparing dialkylzincs to alkylmagnesium halides? The reactions I referred to use organozinc halides which are less reactive. Dialkylmagnesiums are from what I've heard even more reactive than dialkylzincs. Most procedures with organozinc call for an inert atmosphere but so do most Grignards.

[Edited on 19-12-2017 by clearly_not_atara]

JJay - 19-12-2017 at 15:21

Quote: Originally posted by clearly_not_atara  
Quote: Originally posted by JJay  
That's interesting... Grignards are more stable when exposed to air than organozinc reagents...
Where did you hear this? Some organozincs are air-stable period:

http://onlinelibrary.wiley.com/doi/10.1002/chem.201403015/fu...

Are you comparing dialkylzincs to alkylmagnesium halides? The reactions I referred to use organozinc halides which are less reactive. Dialkylmagnesiums are from what I've heard even more reactive than dialkylzincs. Most procedures with organozinc call for an inert atmosphere but so do most Grignards.



I had always thought it would be a good idea to use an inert atmosphere with Grignards, and I was actually comparing dialkylzincs (which is what most people mean when they refer to organozinc compounds) to alkylmagnesium halides and saw that a dialkyl zinc wasn't exactly being formed here or at least not isolated; that was why I asked the question. The paper you cited uses a protecting group to make organozinc compounds air stable, has nothing to do with acetonitrile, and doesn't answer the question.


[Edited on 19-12-2017 by JJay]

clearly_not_atara - 19-12-2017 at 15:37

Organozinc species in THF react slowly with air but do not catch fire ("slow absorption"):

https://www.sciencedirect.com/science/article/pii/0040403995...

I assume that acetonitrile organozinc reagents behave similarly. So the answer is yes an inert atmosphere is certainly required for the Blaise reaction which happens additionally at high temperature.

JJay - 19-12-2017 at 16:19

Fun stuff: https://www.youtube.com/watch?v=EmkBH-ncG1Y

DraconicAcid - 19-12-2017 at 17:53

I'm surprised grignards are stable in acetonitrile. I had thought that it was possible to deprotonate it.

JJay - 19-12-2017 at 19:05

I imagine that the reaction between vanillyl magnesium chloride and acetonitrile followed by acid hydrolysis produces a nice-smelling ketone.

Edit: Oh never mind, that won't work.



[Edited on 20-12-2017 by JJay]

zed - 19-12-2017 at 19:07

Hydrogenation of Acetonitrile, could be one of the better ways to make Di-Ethyl Amine.

clearly_not_atara - 20-12-2017 at 00:31

Quote: Originally posted by DraconicAcid  
I'm surprised grignards are stable in acetonitrile. I had thought that it was possible to deprotonate it.
Since when are Grignards stable in acetonitrile?