wombat (Member)
07-03-99 05:04
No 92030
      Home Made Chloroform and Iodoform     

Methyl ketones and alcohols react with

halogens in base

to produce trihalomethyl ketones. When OH-

is used haloform forms. Thus acetone +

sodium hypochlorite (CHLOROX!) +

NaOH (red devil lye) will give you

chloroform and acetic acid!!  Replacing

acetone with ethanol will give formic acid

instead of acetic acid!

One can you tincture of iodinde and sodium

hypochlorite to make sodium hypoiodide

and then iodoform.

 
 
 
 
    Android
(Member)
07-03-99 15:00
No 92031
      Re: Home Made Chloroform and Iodoform     

Slow down brother!  Your gonna burn up my printer!
 
 
 
 
    CHEM GUY
(Member)
07-03-99 22:12
No 92032
      Re: Home Made Chloroform and Iodoform     

I know of the chloroform synthesis of which you speak and I have the blanced equation but the fromic acid synthesis I haven't seen yet.

So,... could you post the blanced equation for the fromic acid synthesis with NaOCl and/or Ca(OCl)2.

Keep it coming!

 
 
 
 
    CHEM GUY
(Member)
07-03-99 22:18
No 92033
      Re: Home Made Chloroform and Iodoform     

By the way the chloroform synthesis doesn't need NaOH.   One of the products is NaOH, but NaOH isn't nessesary.  I have done this synthesis with just bleach and pure acetone, no added heat or speacal preparation.  Two layers form, one water and one chloroform. 

As for the alcohol synthesis of organic acids I don't know...

One big word of warning; DON't USE CHLorofrom with amines or NH3.  They combine to create posions, isonitriles (AKA isocyanides, or carbylamines<--sp?)

 
 
 
 
    wombat
(Member)
07-03-99 22:48
No 92034
      Re: Home Made Chloroform and Iodoform     

Well ketones add halogens when in basic solution.
The trihalo addition is unique to methyl
ketones and methyl alcohols that are oxidized to methyl ketones. The OH->
hypohalite causes the haloform and a
carboxylic acid to form.

Yes the NaOH is unnecessary since OH- +

halogen -> hypohalite :Cl0- etc.

Thus CH3COCH3 + 3/2Ca(ClO)2 -> COOHCH3 + CHCl3 + 3/2Ca++ +H2O (+O2/2?).

CH3CH2OH + 3/2Ca(ClO)2 -> HCOOH + CHCl3

+ 3/2Ca++ + H2O (+O2/2?).

The ClO- first oxidizes the ethanol

to acetaldehyde CH3CHO.

 
 
 
 
    CHEM GUY
(Member)
07-06-99 14:00
No 92035
      Re: Home Made Chloroform and Iodoform     

Sodium acetate (NaOCOCH3) can be prepared by boiling acetone (CH3COCH3)
with sodium hypochlorite (NaClO) the products are chloroform (CHCL3) and sodium
acetate or for calcium acetate (Ca[OCOCH3]2) use calcium hypochlorite (Ca[ClO]2)

THE EQUATIONS:

2 CH3COCH3  +  3 Ca(ClO)2  -->  2 CHCl3  +  2 Ca(OH)2  +  Ca(OCOCH3)2
  CH3COCH3  +  3 NaClO     -->    CHCl3  +  2 NaOH     +  NaOCOCH3 

Be careful the stronger bleaching powder and the organic can get
 rather busy.
This is a proven source of chloroform and acetate salt.

Now I don'y know the equation for the oxidation of the ethanol to acetaldehyde.  It could be this?

CH3CH2OH + NaOCl --> CH3(CO)H + H2O + NaCl

As for the equation for the oxidation of the acetaldehyde to chloroform,...

2 CH3(CO)H  +  3 Ca(ClO)2  -->  2 CHCl3  +  2 Ca(OH)2  +  Ca(O[CO]H)2
  CH3(CO)H  +  3 NaClO     -->    CHCl3  +  2 NaOH     +  NaO(CO)H 

I would prefer the Ca(OCl)2 for the oxidation because it comes  granular, so you don't have to separate water from the CHCl3. 

Also if you are trying to get acetic acid or formic acid from this reaction you should separate the CHCl3 from the base and salt, either by distillation or evaporation.  I would use HCl gas to make the acid and nuetralize the base.  Once that is done if you've used Ca(OCl)2  the CaCl2 will dry the acid of water and you will have 100% anhydrous acid (either acetic acid or formic acid).

 
 
 
 
    ChemHack
(Member)
07-06-99 20:14
No 92036
      Re: Home Made Chloroform and Iodoform     

Sodium Hypochlorite (bleach) is made by passing chlorine gas through an aqueous solution of sodium hydroxide.  Some sodium hydroxide will remain in the product.

Or to put it another way:  Your Chlorox already contains some NaOH!

 
 
 
 
    ChemHack
(Member)
07-06-99 20:23
No 92037
      Re: Home Made Chloroform and Iodoform     

Oh, and another thing, this is really important so pay the fuck attention!

When you add alcohol or acetone to bleach, not much will happen at first, it takes a little while for the reaction to take off... it is very exothermic!

Now, you may be looking at the half gallon of 5% chlorox thinking to yourself, shesh, if this was more concentrated, I wouldnt be having to use a half gallon of bleach to process a shot glass full of alcohol.

Well, if you can find 10% bleach at the pool shop then you could use it.

RESIST the urge to try pouring alcohol onto a strong solution Calcium Hypochlorite bleaching power or other even strong Soduim Hypochorite.

In higher concentrations the shit gets HOT!

It might not get hot right away, but once the chain rxn gets rolling, watch out!

The temperature will easily surpass the boiling point of the chloroform and it will evaporate away into the air.

Oh well, you tell yourself, I'll just do it in a sealed container... DO NOT DO THIS!  It is a bomb!  It will blow up.  You will get hurt.  You have been warned.

Just play it safe and use the dilute bleach.  The chloroform sinks to the bottom anyway so it will be easy enough to separate.  Please heed my advice.

 
 
 
 
    wombat
(Member)
07-07-99 03:52
No 92038
      Re: Home Made Chloroform and Iodoform     

Oh and another thing, chloroform is toxic,

an anesthetic, and a carcinogen as are

alkyl halides in general.

 
 
 
 
    CHEM GUY
(Member)
07-09-99 16:57
No 92039
      Re: Home Made Chloroform and Iodoform     

Hey there, I found the equation for the hypochlorite oxidation of ethanol.  Here it is,...

4 C2H5OH + 8 Ca(OCl)2 -->  2 CHCl3 + 3 Ca(O[CO]H)2 + 5 CaCl2 + 8 H2O

2 C2H5OH + 4 Na(OCl) -->   CHCl3 + 3 Na(O[CO]H) +  CaCl + 4 H2O

I only found the Ca(OCl)2 equation.  I then used NaOCl in its place and balenced the equation.  So, I think the NaOCl equation is correct.

 
 
 
 
    CHEM GUY
(Member)
07-16-99 15:34
No 92040
      Re: Home Made Chloroform and Iodoform     

In general ethanol is more expensive to get than methanol.  The ethanol usually has impurities in it as well, methanol sometimes.

My question is, What is the oxidation products of hypochloroites with methanol?

Is there a formic acid salt? If so this would be cheaper than using ethanol to make formic acid.

 
 
 
 
    Agent_Smith
(Hive Bee)
05-04-01 12:05
No 189222
      Re: Home Made Chloroform and Iodoform     

I tired this:  Threw about 150ml of 5% bleach (looked slightly greenish) and 100mls of acetone together, stirred.  In a few seconds, the temp crawled up to 50C but never went higher.  The liquid turned piss yellow, with a small ~10-20 ml clear layer on top.  Wheres the chloroform?  In the 230+ mls of piss yellow stuff?  How do I get it out?


blah blah blah something clever blah blah blah
 
 
 
 
    Chromic
(Hive Addict)
05-04-01 13:13
No 189238
      Re: Home Made Chloroform and Iodoform     

You're using waaaaaay too much acetone. Use about 90g per 1 gallon 5.75%, you must use a reflux condenser, sometimes even with external cooling.

If you want a big quantity, you're going to have to think big. Get a big glass carboy, the 5 gallon type (SWIC has one for brewing), rig a long 1m leibig style condenser (copper pipe, 1/2" inner diameter, 3/4" outer) with circulating ice water... (SWIC has one for distilling "moon water") load 4 gallon 10% bleach and slowly add about 650g (you should check these #s) of acetone. Do the addition of acetone by a sep funnel, and do it -slowly-. Let it settle. Pour off the top layer, collect your chloroform from the bottom. Wash with sat. bicarbonate, and fractionally distill your acetone in your still.
 
 
 
 
    Chromic
(Hive Addict)
05-04-01 13:18
No 189239
      Re: Home Made Chloroform and Iodoform     

Btw, what happened is you have a three-component two-phase mixture.

You've got a lot of water, some acetone and a not much chloroform in the bottom layer. You've got a lot of the chloroform, some acetone and not much water in the top layer.

The top layer is floating on water, because you made so little chloroform and the acetone/chloroform mix is less dense than the salt water on the bottom.
 
 
 
 
    Cheapskate
(Downer Dude)
05-04-01 13:23
No 189242
      Re: Home Made Chloroform and Iodoform     

Go over to Rhodium's page and look for Easy preparation of Chloroform.  It works well and quite easily.  In the case you described you only had about 7 mg of sodium hypochlorite to react.  This just isn't enough to produce a substantial amount of chloroform.  What you can do to test this is take about a liter of bleach and drip acetone into it a drop at a time with stirring and watch the bottom of the jar.  You'll see droplets forming on the bottom as you add the acetone.  The heat will rise so don't get carried away.  What you got was a little chloroform an a lot of acetone water mix that will meet your description.

This reaction works, never tried or saw anyone try the others mentioned above.
 
 
 
 
    Agent_Smith
(Hive Bee)
05-04-01 14:22
No 189249
      Re: Home Made Chloroform and Iodoform     

Good to know, thanks guys



blah blah blah something clever blah blah blah
 
 
 
 
    Agent_Smith
(Hive Bee)
05-05-01 19:41
No 189504
      Re: Home Made Chloroform and Iodoform     

One more:  I'm a puss, I don't wanna distill any chloroform, no matter how dangerous it is or is not.

So, in light of that, how bad would it be to simply wash filter and dry it?  (This is a solvent for Os's bromo safrole mehtod, btw)


blah blah blah something clever blah blah blah
 
 
 
 
    goiterjoe
(Hive Bee)
05-06-01 00:53
No 189540
      Re: Home Made Chloroform and Iodoform     

in reply to the first question, I doubt you could make sodium hypoiodide from sodium hypochloride.  the chlorine should have a stronger attraction to the oxygen than the iodine would.


If pacman influenced us, we'd glide around dark rooms eating pills and listen to repetitive music.
 
 
 
 
    Rhodium
(Chief Bee)
05-11-01 16:01
No 193640
      Re: Home Made Chloroform and Iodoform     

Today I found a local chemical supplier selling 99% chloroform in 25L drums for $60 (spring cleaning in their storage room).  25L of anhydrous HPLC quality THF was $120, 2.5L 48% HBr $35 etc... Too bad I have no place to store such drums...


http://rhodium.lycaeum.org
 
 
 
 
    Bwiti
(Hive Bee)
07-10-01 13:40
No 189888
      Re: Home Made Chloroform and Iodoform     

"Wheres the chloroform?"

  If too much acetone is added, don't dump it out. Just add a shit-load of H2O and the chloroform will crash-out. Peace!tongue


  I'm going to help all of you cleanse this diseased planet.
 
 
 
 
    lugh
(Moderator)
08-02-04 18:02
No 523301
      Liebig and Dumas's Version
(Rated as: good read)
    

This prepartion of chloroform claims a slightly higher yield compared to the very similar procedure from Mann and Saunders in ../rhodium/chemistry /chloroform.html, by increasing the amount of hypochlorite relative to acetone wink
 
From Cohen's Practical Organic Chemistry

Chloroform (Trichloromethane), CHCl3.
Liebig, Pogg. Ann., 1831, 23 444; Dumas, Ann. Chim. Phys. 1834, 56 115.
200 grms. bleaching powder (fresh). 800 c.c. water.
40 grms. (50 c.c.) acetone.
A large round flask (4 litres) is fitted with a cork, through which a bent tube passes connecting the flask with a long con­denser and receiver. The flask is placed upon a large sand­bath. Grind the bleaching powder into a paste with 400 c.c. Of water and rinse it into the flask with the remaining 400 c.c. Add the acetone and attach the flask to the condenser. Heat cautiously until the reaction sets in, which is indicated by the frothing of the liquid. Remove the flame for a time, and when the reaction has moderated, boil the contents until no more chloroform distils. This is easily determined by collecting the distillate in a test-tube and observing if any drops of heavy liquid are present. The distillate is shaken with dilute caustic soda solution in a separating funnel and the lower layer of chloroform run into a distilling flask. A few pieces of solid calcium chloride are added and left until the liquid is clear, when it is distilled from the water-bath with a thermometer inserted into the neck of the flask. Yield about 40 grams.
The bleaching powder acts as though it consisted of a compound of calcium hydrate and chlorine, and the process probably occurs in two stages.
1. CH3-CO-CH3+3Cl2=CH3-CO-CC13+3HCl
2. 2CH3-CO-CC13+Ca(OH)2=(CH3-COO)2Ca+2CHC13.
Trichloracetone is first formed, which is then decomposed by the lime into calcium acetate and chloroform.
Proterties.-Colourless liquid possessing a sweet smell, b. p. (60-62°; sp. gr. 1.498 at 15° ; very slightly soluble in water ; non-inflammable. As chloroform slowly decomposes in presence of air and sunlight into phosgene, it is usual to add a little alcohol to the commercial product, which arrests the change. Pure chloroform is neutral to litmus, has no action on silver nitrate solution and does not discolour concentrated sulphuric acid when shaken with it for an hour or left for a day.


cool

Chemistry is our Covalent Bond
 
 
 
 
    Xaja
(Hive Bee)
08-02-04 21:54
No 523337
      Cheapskates method     

Cheapskates method was something like this, was on Rhodiums page once but I can't seem to find it there now...

***FriedPiper***

"Fuck you and the horse you rode in on"
 
 
 
 
    yei
(Stranger)
08-05-04 17:21
No 523895
      continuous reaction?     

I wonder if it would be desireable to try and perform this reaction in a continuous reactor, like one of those spiral condensors, to limit its reaction rate. This might be useful for other reactions as well. (bromination/chlorination?)

It's good to bee back! Don't trust your computer!!