User
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Ethyl chloride/chloroethane prep.
Good afternoon
Can anyone provide a lab prep for the synthesis of ethyl chloride.
Also has anyone experience in this field?
C2H5Cl
Bp: 12.3 C
I found this synthesis but it does require a pressure vessel.
Maybe it can be substituted by a pressure cooker or ordinary reflux likely to kill the yield if even obtained.
Stolen from: Source
Manufacture Of Ethyl Chloride A mixture of alcohol (93 per cent.) and concentrated hydrochloric acid, in the proportion of 40 kilos, of the
former to 100 kilos, of the latter, is carefully heated in a lead-lined autoclave. When the main reaction is over, the temperature is raised to 130°
for about five hours, after which the vessel is allowed to cool down to 50-60° and the liquid distilled into a cooled metal receiver. The product,
which contains a little hydrochloric acid, alcohol, etc., may be rectified from slightly alkaline water to remove these impurities. Alternatively,
before the ethyl chloride vapour is condensed, it may be passed first through a washing vessel containing water to remove acid and alcohol, and then
through a column packed with fragments of earthenware, in which higher-boiling by-products are condensed. Finally it is led through a refrigerator to
a fractionating vessel. From this it is distilled by means of a water-bath, the vapour being passed through strong sulphuric acid contained in a
leaden vessel, and again condensed. The finished product is filled into sealed tubes or flasks for transport and use. In another method the use of an
autoclave is dispensed with, but calcium chloride or zinc chloride is used as a catalyst. If calcium chloride (or other catalyst) is not employed, a
larger proportion of hydrochloric acid must be used. Besides being used as an anaesthetic, ethyl chloride is frequently employed as an alkylating
agent, especially for amines and phenols, in the synthesis of dyestuffs and other chemical products. It is gaseous at the ordinary temperature, the
boiling-point being 12.5°. Its sp. gr. at 0° is 0921.
I wonder if this substance can be stored in fridge/freezer without too much trouble.
Please shoot me if there is already a thread i did search and didn't find a dedicated thread.
When I contain enough lead please delete this thread.
[Edited on 12-2-2010 by User]
What a fine day for chemistry this is.
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entropy51
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I won't shoot you, but it sure is tempting.
Try this one but there are others as well.
Koten (J Chem Ed, Oct 1940, pg 461) gives a synthesis from EtOH, CaCl2, and diethyl sulfate that doesn't require an autoclave.
Here is the classical prep passing HCl into EtOH and ZnCl2. No autoclave is required and yield is said to be quantitative.
[Edited on 12-2-2010 by entropy51]
[Edited on 12-2-2010 by entropy51]
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woelen
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Ethyl chloride can be purchased as a local externally applied aneasthetic for the skin. It is available as spray, slightly pressurized in bottles of
100 ml or so. Look at google under "ethyl chloride spray". It also is available in some tattoo shops for releaving pain and irritation of areas of the
skin which are irritated by recent tattooing.
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gsd
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Quote: Originally posted by User  |
Can anyone provide a lab prep for the synthesis of ethyl chloride.
Also has anyone experience in this field?
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Vogel has a procedure on butanol to butyl chloride using thionyl chloride which should be adaptable here by taking care of the obvious modifications
warranted by very low BP.
I have experience in C4 chlorides not C2 ( those extra 2 Cs makes world of difference and make life hell of a lot easier )
| Quote: Originally posted by User |
C2H5Cl
Bp: 12.3 C
I found this synthesis but it does require a pressure vessel.
Maybe it can be substituted by a pressure cooker or ordinary reflux likely to kill the yield if even obtained.............
|
At atmospheric pressure due to very low reaction temperature, rate of reaction will be extremely low (Arrhenius equation)
In procedure for n-butyl chloride given in Organic Suntheses (http://www.orgsyn.org/orgsyn/default.asp?formgroup=basenp_fo...) this difficulty is slightly overcome by dissolving considerable quantity of ZnCl2
in reaction media thereby increasing the temperature (due to boiling point elevation) without increasing the pressure. However in your case even that
modification is unlikely to yield any workable yield.
It is either pressure vessel or Thionyl chloride.
good luck
gsd
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User
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My guess is that S2Cl2 could do the job as well.
Would for sure be cheaper.
Funny how a couple of C's can ruin your day 
(had too much ethanol yesterday  )
[Edited on 12-2-2010 by User]
What a fine day for chemistry this is.
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bbartlog
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The prep in Barnett - gasing dry HCl through ethanol with fused (dry...) ZnCl2 - is likely to give you better results than trying to adapt the one
from Vogel. I tried the Vogel prep, adapted for isopropyl alcohol, and never got more than 41% yield in four trials. Too much water really seems to
hurt the reaction, and since the Vogel prep uses liquid HCl there is a lot more of it present. I don't think this is because the equilibrium is too
far to the left - after all, the fact that your desired product is being gassed off should make equilibrium considerations fairly irrelevant. Rather I
think that too much water limits the formation of some not-well-characterized zinc-chloro-hydro compound that is actually catalyzing the reaction, and
so slows the reaction rate to a crawl.
Of course, the Barnett prep involves two condensers and four flasks not counting whatever you'd have to put together to provide dry HCl, so your
glassware resources may determine whether you can go that route.
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entropy51
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| Quote: Originally posted by bbartlog | | Rather I think that too much water limits the formation of some not-well-characterized zinc-chloro-hydro compound that is actually catalyzing the
reaction, and so slows the reaction rate to a crawl. |
From what I have read, that is correct.
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User
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I have plenty of glas lying around so thats no problemo.
The synthesis according to barnett seems to be fine.
No exotic nor expensive chemicals.
Dry HCl from NaCl+H2SO4 ?
Seems like this is almost anhydrous by itself.
Ill do some more research and give it a go.
What a fine day for chemistry this is.
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Paddywhacker
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Dry HCl has been prepared by dropping hydrochloric acid onto a large excess of anhydrous calcium chloride.
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gsd
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| Quote: Originally posted by bbartlog | | I tried the Vogel prep, adapted for isopropyl alcohol, and never got more than 41% yield in four trials. Too much water really seems to hurt the
reaction, and since the Vogel prep uses liquid HCl ............. |
Vogel lists both preparations (n-)Butanol to (n-)butyl chloride using liquid HCl +ZnCl2 and (iso)Butanol to (iso)butyl chloride using Thionyl
Chloride.
If you care to read my post I was referring to adapting the 2nd - thionyl one - preparation from Vogel.
There are n+1 number of threads on this topic in this forum.
gsd
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