Author Topic: acetonitrile  (Read 2875 times)

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El_Zorro

  • Guest
acetonitrile
« on: December 17, 2002, 12:16:00 AM »
A cry goes up from the overworked and underpaid minions in Zorro's lab.  Not only do they not get much food, or breaks, or get to see their families, they have no acetonitrile to use in research.  And not only that, they don't want to have to buy it from a chem supplier, because they are also unnecissarily paranoid about such things.  So they want an OTC source if possible.

Well, I can't really argue with them, I mean, they do good work and all.  So what do you bees think?  Is there a good OTC source of acetonitrile?  Or will Zorro have to bite the bullet and order it?

It is seductive, way too seductive.             -Eleusis

SPISSHAK

  • Guest
I dunno
« Reply #1 on: December 17, 2002, 12:54:00 AM »
You know it's not hard to make from acetamide, dehydrate acetamide with P4O10 (phosphorous pentoxide).
What do you want with that chem anyway?

Aurelius

  • Guest
phosphorus pentoxide
« Reply #2 on: December 17, 2002, 01:09:00 AM »
so just how easy is that to obtain (OTC, that is)?

PolytheneSam

  • Guest
CaC2
« Reply #3 on: December 17, 2002, 02:35:00 AM »
You can dehydrate acetamide to acetonitrile using calcium carbide.  I found calcium carbide OTC at a camping store.

http://www.geocities.com/dritte123/PSPF.html


The hardest thing to explain is the obvious

Aurelius

  • Guest
Carbides for dehydration
« Reply #4 on: December 17, 2002, 04:18:00 AM »
how wide an applicability do the carbides have for dehydration reactions?  just amides, or are there others?  (hate to ask, but need to make sure, is acetylene formed- safety issue here)

SPISSHAK

  • Guest
I dunno
« Reply #5 on: December 17, 2002, 06:48:00 AM »
about the applicability of carbides for dehydration, but I can certainly say yes acetylene will be a by-product.
P4O10 is not suspicious at all, I  called one supplier and asked for it they have it, they did'nt ask any questions either, your mileage may vary but I would'nt sweat P4O10 at all.

PolytheneSam

  • Guest
>I dunno I do know.
« Reply #6 on: December 17, 2002, 12:33:00 PM »
>I dunno

I do know.  It says so in a reference I have.

http://www.geocities.com/dritte123/PSPF.html


The hardest thing to explain is the obvious

Aurelius

  • Guest
PolytheneSam
« Reply #7 on: December 17, 2002, 08:43:00 PM »
So, just how many different types of compounds can it be used to dehydrate? what are they?  apparently, we have a nice way to cyanides.

PolytheneSam

  • Guest
alcohol
« Reply #8 on: December 17, 2002, 08:51:00 PM »
I saw a couple books in the library which said that it can be used to dry alcohol.  It seems to work similar to CaO.  I haven't seen CaO (quicklime) OTC anywhere.

http://www.geocities.com/dritte123/PSPF.html


The hardest thing to explain is the obvious

El_Zorro

  • Guest
I know calcium carbide is pretty otc, but didn't ...
« Reply #9 on: December 18, 2002, 01:30:00 AM »
I know calcium carbide is pretty otc, but didn't know I could use it to dehydrate acetamide.  Does anyone have a ref or procedure for this?

It is seductive, way too seductive.             -Eleusis

Captain_Mission

  • Guest
acetonitrile
« Reply #10 on: December 21, 2002, 12:10:00 AM »
If you can get NaCN or KCN you can make acetonitrile out of it and dimethylsulphate. Solvents used are DMSO, tri-ethyleneglycol or ethyleneglycol. Here´s one of the procedures, translated and adapted from ORGANIKUM, 5th edition:

 In a 1000ml 3neck RB flask, with a stirrer, reflux condenser and thermometer are heated, with good stirring, 250ml of triethyleneglycol, 1,5 mol of dried and powdered NaCN and 1 mol of alkyl halide(or 0,5 mol of alkyl sulphate). The beginning of the reaction is apparent by the boiling of the reaction mixture. The temperature is slowly raised to 140°C and the reaction is stirred at this temperature for 30 minutes.(...) Lower nitriles, beeing soluble in water and volatile, are seoarated from the reaction mixture by direct distilation(...), washed withsaturated NaCl solution, dried over CaCl2 and re-distilled with a 30cm vigreux column.(...)

Yield for acetonitrile, using dimethylsulphate, 75%.
Using DMSO: JOC 25,257(1960), and JOC 25,877(1960)

I´ll try to find the one using ethyleneglycol to post it here.

Other references wich might be useful:
 Houben-Weyl. vol. VIII pg290-311(1952)
 Chem. Reviews 42 189-284 (1948)

El_Zorro

  • Guest
Well shit, if I had access to NaCN and DMS, then ...
« Reply #11 on: December 22, 2002, 03:01:00 AM »
Well shit, if I had access to NaCN and DMS, then I'd most likely have access to acetonitrile, and I'd use the DMS for other stuff.

It is seductive, way too seductive.             -Eleusis

Captain_Mission

  • Guest
from JACS vol 74 pg840, 1952 Synthesis of ...
« Reply #12 on: December 22, 2002, 06:00:00 PM »
from JACS vol 74 pg840, 1952
Synthesis of Nitriles in Ethylene Glycol(1)

Low-boiling nitriles cannot be made from alkyl halides and sodium cyanine in aqueous alcohol because of the difficulty of isolating the products from the solvent. However, other solvents which dissolve appreciable amourlts of sodium cyanide can be used. Thus, ethylene glycol has been used in the preparation of 5-hexenonitrile from 5-bromo-1-pentene(2), and its monoalkyl ethers, as well as tetrahydrofurfuryl alcohol, have been used in the preparation of succinonitrile and adiponitrile.
There are relatively few examples in the literature of the formation of secondary cyanides by displacement reactions, and none at all of tertiary cyanides. Low yields in these reactions are commonly attributed to olefin formation(4), but there have been no quantitative studies to bear this out.
Several of the solvents tried were found to be quite unsatisfactory. n-Butyl bromide was largely unchanged after a 40-hour reflux with sodium cyanide in n-butyl cellosolve or nitrobenzene. t-Butyl chloride in t-butyl alcohol gave a high yield of isobutylene.
i-Butyl bromide in hydrogen cyanide gave a little olefin along with unidentifiable material, although the sodium cyanide dissolved in the hydrogen cyanide to the extent of 0.54 g. per 100 cc. t-Butyl bromide in cold saturated aqueous sodium cyanide gave only a black tar.
Ethylene glycol proved to be a much more suitable solvent, even though it is not miscible with the alkyl halides. Table I shows the results of experiments with several primary, secondary and tertiary halides. In all runs there is some loss in the form of undistillable black residues. Other than this, the main side-reaction is the formation of glycol monoalkyl ethers (solvolysis), olefins are a relatively minor product.
The reactions with the primary halides were particularly gratifying. Valeronitrile, for instance, was prepared in 90% yield after one hour of reflux, and was readily separated from the reaction mixture by distillation. The best yield reported in aqueous alcohol after 25-30 hours of reflux and a careful, 10-hour distillation is 80%(5). Butyronitrile has been made in aqueous alcohol, but not isolated.(6)

TABLE I
REACTION OF ALKYL HALIDES WITH SODIUM CYANIDE
              Initial        Reaction
Alkyl          temp.,         time          Yield, %
halide           C.            hr.    Nitrile Ether  Olefin
          
n-BuBr          101             1       90
n-PrBr           72             1       92
i-PrBr           60            24       39
i-PrBr(a)        60            15       39     16       7
s-BuBr(a)        92             4       28     Low
s-BuCl           68            22       No reaction
t-BuBr(a)        73            3(b)     Low     44
t-BuC1           50             6       Low     41
t-BuC1(a)        46             6       10(c)   27      18

(a)Sulfuric acid added. (b)Reaction seemed to be complete
in one hour. (c)Impurities may reduce this to about 5%.

-table II(identification of products) omited(just b.p´s of the above compounds) -

Although the yields of secondary cyanides are only fair, the fact that they can be easily obtained in a single step may make the reaction useful. Isobutyronitrile, for instance, cannot be made in aqueous alcohol, and is difficult to make by indirect methods. It is doubtful whether this method of preparing t-butyl cyanide (pivalonitrile) is practical.
In a few runs part of the excess sodium cyanide was neutralized with sulfuric acid in an attempt to reduce the over-all alkalinity. This reduced the proportion of glycol ether in the product; the effect was small, however, and it was concluded that the alkoxide ion, HOCH2CH2O-, which might have been present in the unbuffered solution, was
not directly responsible for ether formation.

Experimental

The alkyl halides and ethylene glycol were redistilled before use. The sodium cyanide was Baker Analyzed, 98% minimum.
The general procedure was to mix 150 cc. of ethylene glycol, 0.5 mole of the alkyl halide and 0.55 mole of sodium cyanide in a 500cc. three-necked flask, and to heat under reflux with constant stirring until the end of the reaction.
The initial temperature, measured by a thermometer in the vapor, was always close to the boiling point af the halide, and the end of the reaction was marked by a rapid rise in
termperature to a constant value as the last of the halide was used up. In a few runs 0.1 mole of sulfuric acid and an additional 0.2 mole of sodium cyanide were added before heating. In the reaction with n-butyl bromide it was observed that the heat of reaction was sufficient to maintain spontaneous reflux at the start.
The liquid products were distilled from the reaction mixture through a three-ball Snyder column. Where further purification of the nitriles was required they were washed with 4 N hydrochloric acid, 10% sodium bicarbonate and water, dried and redistilled through a 9inch or 18-inch packed column. Their properties are listed in Table II. The odor revealed that traces of isocyanide were still present in all cases.
In the runs in which olefin was determined the evolved gases were passed through soda-lime to remove hydrogen cyanide, and condensed in a trap at -80C. The olefins were then converted to the dibromides by passing them into a sodium tribromide solution, prepared from 70 g. of sodium bromide, 112 g. of bromine and 300 cc. of water. The dibromides were washed with sodium carbonate and sodium thiosulfate solutions, dried and weighed.

(1) From the M. S. thesis of Peter V. Susi, September, 1951
(2) F. B. LaForge, N. Green and W. A. Gersdorff, THIS JOURNAL, 70, 3707 (1948).
(3) A. O. Rogets, USPatent 2,416,261, Feb 4 1917
(4) D.T. Morey, Chem. revs. 42, 189 (1948)
(5) R. Adams and C.S. Marvel, THIS JOURNAL, 42,310(1920)
(6) K.W. Rosenmund, K. Luxat and W. Tiedemann, Ber. 56,1950 (1923)

------------------------------------------------------------
Well shit, where do you get your acetamide and phosphorus pentoxide/boric oxide from, anyway? The grocery? And how the fuck would I know what you can or cannot get?  If you have access to MeOH and H2SO4, with good equipment you can make DMS. And there are numerous ways posted here to make NaCN out of more OTC materials. This shouldn´t be more work than making acetamide and fucking Boric oxide, wich would require very high temperatures to make, and I´ll just leave P2O5 alone. 
 
I don´t want to start a discussion but I´m upset because I took the time to translate that procedure and edit this article to text format just to get flamed. I´m sympathetic with you on the aquisition problem, as I myself can´t get neither NaCN nor DMS, nor can I get acetonitrile. I just wanted to provide another way to solve it than the ones discussed.

And another interesting thing in this article is their procedure for making the dibromides of the olefin byproducts.  They use 0.68 mol NaBr to 0.75 mol Br2 in 300ml of water. Maybe the dibromide of isosafrole(or any other propenyl benzene) can be made with in situ generation of Br2.  This is a new thing for me, I alway thought that, with water present,  the bromohydrin would be formed instead. But this discussion is better left to another thread. 

Captain_Mission

  • Guest
5 minutes on TFSE...
« Reply #13 on: December 22, 2002, 06:36:00 PM »

Post 378009

(Wraith: "Easy KCN from ferrocyanides w/out HCN", Chemicals & Equipment)

https://www.thevespiary.org/rhodium/Rhodium/chemistry/nacn.txt


Post 57287 (missing)

(uemura: "Dreams of a KCN synthesis", Methods Discourse)

Post 208329

(halfapint: "Re: OTC preperation of Dimethyl sulfate?", Tryptamine Chemistry)

El_Zorro

  • Guest
Sorry dude, wasn't really trying to flame you.
« Reply #14 on: December 22, 2002, 09:58:00 PM »
Sorry dude,  wasn't really trying to flame you.  That was definately an exellent procedure you posted, as well as the one from alkyl halides, too.  But I was really looking for a bit more OTC method. 

I was more interested in the dehydration of acetamide with calcium carbide.  Acetamide is pretty easy to make from GAA and urea, and calcium carbide is faily OTC.  Again, I wasn't really trying to flame you, I was just looking for more of an OTC method that had more of a industrial application.

It is seductive, way too seductive.             -Eleusis

Captain_Mission

  • Guest
Sorry for beeing so aggressive.
« Reply #15 on: December 25, 2002, 04:08:00 AM »
Sorry for beeing so aggressive. I overreacted to your post. I´ve been a little upset lately, maybe it´s all this bullshit about christmas getting to my nerves.

 As I said above, it all comes down to availability of reagents. If you have easy access to CaC2 then that´s much less trouble to go that way than follow that stuff I wrote.
But both are fairly OTC in their own way, if you are willing to to prepare everything from scratch.
Boric Oxide, if it works OK, should also be a very good OTC choice, as it is used in glass making and in ceramics and should not be very difficult to prepare from Boric acid.


El_Zorro

  • Guest
That's alright, dude, I know how you feel.
« Reply #16 on: December 25, 2002, 09:36:00 AM »
That's alright, dude, I know how you feel.

But if anybody has a procedure for dehydrating acetamide with calcium carbide, I'd love it.  I have some 20 odd grams of AR grade acetamide laying around, and it ain't enough to make a worthwhile amount of methylamine, so why not experiment with some acetonitrile, right?

It is seductive, way too seductive.             -Eleusis

PolytheneSam

  • Guest
Look what else you can do with calcium ...
« Reply #17 on: January 02, 2003, 03:59:00 AM »
Look what else you can do with calcium carbide.

Patent US2585969




El_Zorro

  • Guest
So how does one add the carbide to the ...
« Reply #18 on: January 02, 2003, 07:31:00 AM »
So how does one add the carbide to the acetamide?  That patent just said to add a mixture of carbide and KOH to their substrate.  So were they just ground together and added as solids?  In what solvent should the substrate be dissolved in?


ylid

  • Guest
OTC acetonitrile
« Reply #19 on: April 09, 2003, 10:46:00 AM »
There is an industrial solvent out there that contains 30% acetonitrile and 70% IPA, which I would imagine might be ideal for condensation with 2,5-methoxy-benzaldehyde straight from the bottle. I can't say more without giving the source away, if indeed it has not already been burnt down. Keep searching those MSDS sheets.