What would be the product from bubbling Cl2 through methanon? would this be a good way to produce dichloromethane?
And just a side thought, what about the product from chlorination of isopropyl or isobutyl alcohol?Esplosivo - 16-6-2004 at 21:32
Chlorination by direct action of Cl2 on the alcohol will not remove the -OH group and will cause a mixture of compounds to form. If you want
dichloromethane you will have first have to oxidize the methanol to methanal (by K/Na dichromate) and then react with PCl5. Not that simple ain't
it Reverend Necroticus Rex - 17-6-2004 at 06:54
Would KMnO4 be sufficient to oxidise the methanol? Just out of interest, what would be formed by direct chlorination?Esplosivo - 17-6-2004 at 07:23
KMnO4 would oxidize the methanol to the respective acid that is methanoic acid. KMnO4 is too strong an oxidizing agent to oxidize the methanol only to
the aldehyde. I am not sure about the products of direct chlorination though. Maybe some one else can help.Reverend Necroticus Rex - 17-6-2004 at 07:27
What about overoxidising with KMnO4, than adding a mild reducing agent, something that wouldn't be strong enough to take it back to methanol?Esplosivo - 17-6-2004 at 07:35
Don't know any reducing agent which would reduce the carboxylic acid to the aldehyde (except those used in industry which are complex and start
from methanol to produce the aldehyde). To reduce a carboxylic acid you need some strong reducing agent such as Lithium Aluminium Hydride, which being
a strong reducing agent causes the rxn to continue and produce the alcohol.unionised - 17-6-2004 at 11:01
[Edited on 17-6-2004 by unionised]Reverend Necroticus Rex - 17-6-2004 at 11:51
Yeah, I guessed that, but what exactly would be generated? knowing me, I can turn it to some use The_Davster - 17-6-2004 at 11:52
Methanol can also be converted to methanal by using a hot(red hot) copper or platinum wire. You could pass methanol vapours through a copper pipe
filled with copper wool while the pipe is being very strongly heated. What would come out the other side is a mix of formaldehyde and unreacted
methanol vapours, this would have to of course be bubbled into water.
Not that one wants to work with hot methanol vapours and an open flame heat source...Reverend Necroticus Rex - 17-6-2004 at 11:54
I might have to give that a try, but copper wool? where would I get that, I have only ever seen steel/iron wool over here?
Do you think iron wool with fine copper powder mixed throughout it might do the trick?
[Edited on 17-6-2004 by Reverend Necroticus Rex]The_Davster - 17-6-2004 at 12:30
I just saw copper wool at safeway today. It was in the household cleaner section. But before you give this method a try search around this site, I
believe that somewhere it says how to make safety devices into it to prevent accidental explosions.vulture - 17-6-2004 at 12:32
Quote:
Yeah, I guessed that, but what exactly would be generated? knowing me, I can turn it to some use
You could perhaps check the linked
thread???
Use google and the forum search engine!
If you're even too lazy to check out links that others provided you with, well then expect to be banned (AGAIN) soon.
Yes, I know who you are.
[Edited on 17-6-2004 by vulture]
[Edited on 17-6-2004 by vulture]Reverend Necroticus Rex - 17-6-2004 at 13:00
Thanks, I missed it the first time I looked.
bis-chloromethyl ether is frightful, Could you post a link to an MSDS for it? I can't find one on google, thanks.t_Pyro - 17-6-2004 at 19:02
This link should answer your questions. Google does work.Reverend Necroticus Rex - 18-6-2004 at 07:44
Yeah, I found those, there dosen't seem to be an msds for it though, only warnings about it being formed from HCl+methanol, and a few procedures
and such for it's disposal. No matter.Mendeleev - 18-6-2004 at 09:35
This is probably less relevant to the author of this thread as he lives in Great Britain, and most likely does not have the same products as in the
USA, but in the USA Klean Strip KS-3 paint stripper and remover is 85-90% DCM according to the msds. The rest is ethanol toluene and acetone. So
distill at 45-50 degrees and you should get at least 3 L of DCM and the cost is $10 a gallon for the remover. It is sold in Home Depot, but I
don't think Lowes carries that brand.Reverend Necroticus Rex - 18-6-2004 at 09:38
I haven't yet found DCM in paint remover over here, I have however found it as the solvent in some aerosol glues, it's just that the
distillation is a pain because of all the nasty gluey mess that gets left behind unionised - 19-6-2004 at 09:32
You need to produce an msds for any material you want to sell or transport. Bis CME is so nasty that nobody sells it so there isn't a data sheet.
Last time I checked, nitromoors paint stripper was based on dichloromethane.Mendeleev - 19-6-2004 at 11:21
Well here's an MSDS for KS3 paint remover, around 80-85% DCM.
Attachment: KS-3 Remover.pdf (169kB) This file has been downloaded 1048 times
BromicAcid - 20-6-2004 at 15:08
Chlorination of methanol with either sulfur or phosphorus present supposedly yields a good percentage of tetrachloromethane. It was one of the
methods that I researched for the formation of this specific product and is used industrially.Reverend Necroticus Rex - 20-6-2004 at 15:12
Please post some more details on that, do you mean chlorination in the prescence of elemental sulphur?
also I'm rather worried about formation of ANY bis-chloromethyl ether, that stuff looks nasty in the extremeBromicAcid - 20-6-2004 at 15:31
I don't have any reference material but I remember the reaction takes place under pressure but it is not some unattainable pressure.
I theorize the initial step is analogous to the reaction of methane with sulfur then the thus formed carbon disulfide would readily react with the
chlorine or sulfur chlorides looks like some sulfur would be lost this way though:
I have no references to indicate that bis-chloromethyl ether is formed but I would assume it is considering it is formed under similar reactions.
Edit: What am I thinking leaving H2S in there with chlorine being pumped into solution? The H2S would instantly react to HCl and SCl2 therefore the
overall balanced equation could be:
CH3OH + 3Cl2 --(S)--> CCl4 + 2HCl + H2O
[Edited on 6/21/2004 by BromicAcid]Theoretic - 20-10-2004 at 06:36
Dehydrogenating methanol to formaldehyde, then reacting it with SOCl2 (not PCl5) is a viable method, since SOCl2 is much easier to get than PCl5.ctrlphreak - 23-9-2008 at 09:12
Idon't want to be an asshole, but why can't you hydrochlorinate methanol to methyl chloride, have that distilled over, and then further chlorinate it?ScienceSquirrel - 23-9-2008 at 09:20
Quote:
Originally posted by ctrlphreak
Idon't want to be an asshole, but why can't you hydrochlorinate methanol to methyl chloride, have that distilled over, and then further chlorinate it?
Methyl chloride is a gas bp -24.2 C so it is a pig to handle.
Also gas phase chlorinations are a mad pig in the lab, the whole thing could run out of control and explode. DJF90 - 23-9-2008 at 09:21
Hydrochlorinate? You mean use HCl in a nucleophillic substitution reaction? I dont think it would work like that but I need to polish up on my
substition/elimination "rules"... As for the further chlorination, there are many side products as it is free radical substitution occuring (unless
you have another method?) and these variety of products can be difficult to separate.Sauron - 23-9-2008 at 14:42
Using thionyl chloride on methanol gets you SO2, HCl and MeCl, three gases, which would need to be seperated. A bit of a muddle.
An elegant way to prepare methyl chloride is th react cyanuric chloride with methanol (excess methanol) at 15 C below reflux, then cold trap the MeCl.
No HCl is produced. A dry ice/alcohol dewar condenser will do fine and the MeCl can be stores in a lecture bottle or (better) Sure/Pac cylinder with a
brass control valve till needed. There's an article in JACS on this method of preparing alkyl chlorides from alcohols and I have posted it previously.
For some idea of what might happen on direct chlorination of methanol with Cl2, consider carefully the elemental chlorination of ethanol. Ethanol is
oxidized by chlorine to acetaldehyde, probably via ethyl hypochlorite. Acetaldehyde is smoothly chlorinated to mainly dichloroacetaldehyde, then the
chlorination slows and becomes less efficient while the final chlorine is added to produce chloral (trichloroacetaldehyde).
Therefore I suggest to you that methyl hypochlorite as intermediate to formaldehyde (methanal) is a BAD IDEA as it tends to go BOOM and in any case
formaldehyde is not going to yield any MeCl or DCM.
