04-18-01 19:10
No 185026
The Nitroalkane Preparation FAQ describes the synthesis of nitromethane with mono-chloroacetic acid. Would it be possible to get nitroethane from mono-chloropropionic acid ?
(Chief Bee)
04-19-01 01:16
No 185108
No, that reaction will only work with mono-chloroacetic acid. The intermediate 1-nitroacetic acid is decarboxylated because it has only the electron-withdrawing nitro group on the side chain, while 1-nitropropionic acid would also have a methyl group there, making it more stable.
http://rhodium.lycaeum.org
(Stranger)
04-19-01 18:47
No 185290
Not quite so. Problem seems to bee not in ease of decarboxylation, but rather in O/N alkylation selectivity,
which in more sterically congested haloacids shifts toward O and gives wrong products. Nevertheless, I have reference to: V. Auger, Bull. Soc. chim. France [3], 23, 333 (1900) ,which claims, that using alpha-bromopropionic acid in Kolbe method gives nitroethan with yield 50% (thats even better than nitromethane yield from chloroacetic acid) No, I don't have original paper and don't know, if the methodics differs from nitromethane one. Alpha-bromopropionic acid one can probably make from lactic acid and hydrobromic acid boiling them together and distilling or something, but don't quote me on that.
(Chief Bee)
04-19-01 20:48
No 185311
Alpha-bromopropionic acid can be made from propionic acid, Br2 and PBr3 (or red P). It is also a name reaction, but I have forgotten the name.
http://rhodium.lycaeum.org
(Newbee)
04-19-01 21:42
No 185319
Rhodium, Greensnake thanks for this information.
BTW: á-Bromopropionic acid may be prepared in 80–85 per cent yields by bromination of propionic acid, the general procedure given for á-bromoisovaleric acid (Org. Syn. 20, 106) being followed and a fraction boiling at 100–102° at 15 mm. being collected.
(Hive Addict)
04-21-01 02:37
No 185566
Rhodium, it's the Hell-Volhard-Zelinsky Rxn you were after.
not that it helps a whole lot, but there you go. maybe it'll bring back some memories of your Orgo I days.
(Newbee)
04-26-01 13:14
No 187031
Beilstein 1,100: alpha-bromopropionic acid + K2CO3 + NaNO2 + H2O --distillation--> nitroethane (50%) (Auger, Bl.{3}23,333)
(Chief Bee)
04-27-01 04:29
No 187153
!!! Could someone get that reference for us?
http://rhodium.lycaeum.org
(Hive Bee)
04-29-01 17:50
No 187888
It goes something like this (my frence is not that god)
add 20g acid to a 20% solution of potasiumcarbonate in such amounth that the solution is basic on phenolphtalin. Then add 20g sodiummnitrit you now have app. 100mL solution.
Add the solution to a 250cc round bottom bulp. Mount a claisen and start destilate with good heath. After the first 100cc has distilatet the reaction takes plase and the nitroethane comes ower, distil until no more product comes ower. yeald app 50%
I'll give it a shot :-)
(Hive Bee)
04-29-01 20:16
No 187908
Wonderfull with another astonish sucses, yeald 18% of not so pure nitroethane ho ho ho. I'll gues that the frog is a beather chemist than mee (or full of lie)
(Stranger)
05-02-01 07:13
No 188519
hum...
Hum did you get that?
(Stoni's sexual toy)
05-02-01 13:36
No 188606
According to J. Chem. Soc. 109, 701 (1916) ethyl nitrite can be converted to nitroethane at 120-130°C with an asbestos catalyst.
(Newbee)
05-02-01 16:45
No 188626
oh my dear friends.
this is not the first time that nitroethane acquisition was discussed here. so like it's been once suggested that one could reduce acetonitrile to ethylamine and then oxidize it. We discussed it with Psyloxy and he told me that dimethyldioxirane would do the job, with excellent yields. i consulted my friends and, can you imagine, it's made really easily. so i decided to put it here. might be useful to someone. that's how it's made.
to conc. H2SO4 there's added an equal volume of 30%H2O2. Slowly and with cooling. chill to ambient t. then add some acetone slowly, stirring, ice bath. smell it. then add more acetone. when the rxn over it begins to smell of acetone. by that time the soln is filled with white DMDO (insol in water, sol in acetone, ether). wait for 30 min for the rxn to complete. filter. then wash really well, tasting it periodically (not poisonous) - must not be sour. IMPORTANT!!! it will be unstable otherwise. and really easily detonated. will tear your fingers off if you're not careful w/it. in one report 10g of it blew a 3 inch hole in the window sill on which it lay as well as tore apart a 1/4 inch thick screwdriver! with which the uncareful chemist decided to pluck it to see if it's dry. so wash it really well. if pure, it's not that dangerous, as well as in the soln. don't hit it though.
well that's it.
PSYLOXY CAN YOU ELABORATE ON HOW TO DO THE OXIDATION? I am really interested in this 'cause that's how i plan to make nitromethane - lucky you americans, have it OTC - shit i'm so envious :):):)
(Stoni's sexual toy)
05-02-01 18:30
No 188642
Well, I guess all the Americans are jealous of you because you can get the MeNH2
(Hive Bee)
05-02-01 20:16
No 188663
Antoncho, y'r joking right ?
cyclic peroxides from acetone is not wise to make, they are very unstable and quite explosives, a lot of kids blow off their fingers with this stuff when they try to make a homemade bomb.
(Hive Addict)
05-02-01 21:45
No 188681
Check out this forum
They have a whole bunch about acetone peroxide, making it safety ect.
The shit sounds dangerous, it would bee easy to get busted/dead if a little of it blew up.
Do Your Part To Win The War
(Hive Bee)
05-03-01 02:44
No 188750
If sodium nitrite can be obtained, there are many safer routes to nitromethane. Perhaps the simplest would be to use the nitration of methanol by means of the method on Rhodium's page. This method hasn't been optimized yet, but IMHO it's worth the effort. Other published approaches are from chloroacetic acid and sodium nitrite (Organic Syntheses, Vol 3 p 83) or from dimethyl sulfate and sodium nitrite (Ber. Deut. Chem. Gesell. 40, 3214, 1907). Direct nitration of propane will produce a mixture of nitromethane, nitroethane and nitropropane, and can be done in electrically heated aluminum tubing using nitrogen dioxide as the nitro source. It's rather likely that methane can be nitrated similarly. If you are experienced in very hazardous synthesis, what you propose may be feasible, but explosives are unforgiving, to say the least.
(Hive Addict)
05-03-01 03:44
No 188772
They have a whole bunch about acetone peroxide, making it safety ect
I spent a year working at a chemical plant that made organic peroxides including methyl ethyl ketone hydroperoxide (MEKP). My opinion is that the term "making acetone peroxide safely" is an oxymoron of the highest degree. Over the years at this plant a number of people had died in explosions and flash fires. I found another job after a year partly because I didn't think I was getting paid enough money for the risks I was taking. One night, shortly after I quit, there was an explosion in the MEKP production building. I heard the explosion at my apartment 20 miles away. The production building had heavily reinforced concrete walls probably 6 inches thick and a lightly attached wooden roof. The intent of the building design was to direct the force of an explosion upwards. It didn't work. The contents of the building and the 6 inch thick reinforced concrete walls were "vaporized" in the explosion.
(Newbee)
05-03-01 14:33
No 188893
uhh... i see. But (correct me if i'm wrong) is it not true that DMDO won't explode if in solution or wet (AND handled w/care)? At least, most peroxides i've heard of don't (
By the way, methylamine in Russia is, i believe, as available as in the US - it's watched. But one can make it from camping fuel. Chloroacetic costs a fortune (and the yield from it really sucks!).
The nitration of eth/methanol does look promising, though. Unfortunately, no one knows if it works on lower alcohols. Has anyone here had any practical experience with it? I have a strong feel that it might benefit from totally unhydrous conditions and , maybe, microwave irradiation.
(Stoni's sexual toy)
05-03-01 15:32
No 188900
> The nitration of eth/methanol does look promising, though. Unfortunately, no one knows
> if it works on lower alcohols. Has anyone here had any practical experience with it?
Hold on, what do you mean? The procedure I gave starts with nitrite esters (easily available from alcohols, NaNO2, and some strong acid). And the other procedure mentioned here uses vapour phase nitration of alkanes, which is too difficult for the ghetto chemist, unless you invest LOTS of money and plan to build a continuous production apparatus.
(Hive Addict)
05-03-01 21:37
No 188946
Last I checked, acetone peroxide is not dimethyldioxirane (DMDO). DMDO is like acetone, but instead of (CH3)2C=O you have (CH3)2C=(O-O).
Acetone peroxide is a cyclic species that likes to explode.
(Hive Bee)
05-04-01 02:32
No 189039
The alcohol nitration procedure referred to is on Rhodium's page at: http://rhodium.lycaeum.org/chemistry/alc
(Hive Addict)
05-04-01 03:43
No 189058
Last I checked, acetone peroxide is not dimethyldioxirane (DMDO). DMDO is like acetone, but instead of (CH3)2C=O you have (CH3)2C=(O-O).
Acetone peroxide is a cyclic species that likes to explode.
True that DMDO is different from cyclic acteone peroxide. DMDO is cyclic though - one carbon and two oxygens for a ring isn't it? In any event, I thought that DMDO also liked to explode too. Acetone and methyl ethyl ketone hydroperoxides will certainly explode, they just aren't quite as shock sensitive as the cyclic forms.
(Delicioso!)
05-09-01 17:41
No 192966
for what it is worth the synth from sodium ethyl sulfate and NaNO2 runs fine, it uses a fair bit of NaNO2 for the amount nitroethane produced
100g NaNO2 + 160g NaHEtSO4 + (catalytic amount)KHCO3 + heat =yeilded 25g nitroethane and a similar amount of what is assumed to be ethyl nitrite, that disappears in the water wash.
yeild ca 30% (yeilds could be improved by mixing reagents better than was done for this experiment)
rxn goes quik, 1/2 hour. its making the sodium ethyl sulfate that is tedious.
i'll warn ya though you need a shitload of headroom cuz the rxn foams ALOT! like a 2l flask for the above size rxn.
that other route via ethanol and NaNO2 also runs (triied nanonscale), but uses HUGE amounts of DCM that has to be stripped off, so it is volumetrically problematic. if i remember its like 250mls DCM to get a couple mls nitroproduct.
methods that scales better would sure be nice.
btw - how were they planning on oxidizing the ethylamine?
as in cobalt
(Stoni's sexual toy)
05-09-01 20:17
No 192991
Nobody interested in the ethyl nitrite conversion?
Pfffffft.
(Delicioso!)
05-09-01 20:50
No 192997
I'm all ears Os, just have to take a day off work to get to the library before i'm in any position to comment.
it's similar to whats going on the sodium ethyl sulfate synth as well isn't it (minus the nitration)?
as in cobalt
(Hive Addict)
05-09-01 23:17
No 193036
can't remember exactly , but the sodium nitrite and ethanol does work at the either 50 or 500x scale to what's on Rhodium's site. (try without the DCM- didn't want to mess with the solvent volume, so left it out-worked just fine) just filter, wash, distill- however you want to purify.
(Chief Bee)
05-10-01 00:24
No 193054
Obit: I am very interested in a detailed writeup on that scale-up, including yields and stuff like that.
http://rhodium.lycaeum.org
(Hive Bee)
05-13-01 13:51
No 194007
Yes, Obit: please clarify. Are you implying that you put sodium nitrite in ethanol, added acetic acid then hydrochloric acid, and casually distilled off a whole bunch of nitroethane? Because that would bee big news around here! TIA...
Half a pint's a half a pound, a half the world around, around.
(Hive Addict)
05-14-01 23:05
No 194378
sorry for the long wait but obit has been out of town for a while and will re-run the rxn and post the results, it's been to long for this short-memory bee to remember the details. get back with ya- hopefully with good news.