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JoeJablomy
February 13th, 2004, 03:06 AM
I couldn't find anything elsewhere on the synthesis of malodorants. Anyone who's read the patents referred to in the patents thread knows that alkyl mercaptans with some skatole carried in vegetable oil can apparently be used, and I did find this for at least the structure of skatole:

http://www.bris.ac.uk/Depts/Chemistry/MOTM/silly/sillymols.htm
(about 1/4 the way down)

I don't know about KOH and egg whites, and the site is fucking stupid, but hopefully the structure will be useful.
So, for those of you that do know something about chemistry, how would you go about making

n-butyl mercaptan
methyl mercaptan
skatole
putrescine
cadaverine
or, for that matter,
"a malodorant organic sulfur compound; organic nitrogen compound; organic phosphorus compound; substituted or unsubstituted C.sub.3 to C.sub.6 aliphatic or cycloaliphatic carboxylic acid, aldehyde or acid halide; aliphatic diyne; inorganic silane; allyl trifluoro acetate; cis-4-decanal; pentafluoropropionic anhydride; 6,6-dimethylfulvene; methyl 4-methylbenzoate; or a mixture of two or more of the foregoing."?

Ethyl and methyl mercaptans are supposedly the stuff they put in natural gas so it stinks, so they should be pretty cheap; really most of these at least in the first part of the list seem like pretty simple compounds. And I have to say, at least with my sense of humor, I'd bet this kind of chemical warfare, applied to the correct persons who are abandoning their duty to uphold the constitution...

Sparky
February 15th, 2004, 12:44 AM
This is a little off topic, but it's a little idea I thought I would share.

If one were to take the oderant used in propane and disperse a little bit of it throughout a building, the occupants would think there was large amounts of propane filling the building. This would of course lead to an evacuation since everyone would think there was a big fire / explosion hazard. Flushing people out of a building like this could be useful. Specific uses I leave to your imagination. Certainly it's much more original than pulling the fire alarm. I wonder how the fire department would respond.

zeocrash
February 15th, 2004, 05:20 AM
Putrescine and cadaverine (sp?) are all standard diamines, these could be produced by simple hydrolosis of various types of nylon (putrescine - nylon 4,x ; cadaverine - nylon 5,x) and then the separation of the dicarboxylic acid crystals and the diamine.

Efraim_barkbit
February 15th, 2004, 05:24 AM
Look in the thread "stink bomb (http://www.roguesci.org/theforum/showthread.php?t=3212&highlight=stink+bomb) " for a Ethyl mercaptane synthesis.

JoeJablomy
February 15th, 2004, 08:20 AM
Thanks for the link. I should have looked for something like "stink bomb," but I guess it was too obvious :)
The bit about butyric acid looks interesting; can it be distilled from the crude butter acid to get better potency?
What temp does H2S condense at? I've always been a bit skeptical about bubbling-gas-through-liquid procedures because of the gas escaping. Or does it? The one time I tried something like that the feed gas came through in increasing amounts as the solution was depleted, and leaking large amounts of H2S would be a bit of a giveaway. Can a one step process with metal sulfide and ethanol be used? It seems to me that water is essentially a catalyst in this process, so perhaps standard 95% grain alcohol could be used with the right amount of sulfide in a pressure vessel or something.
3H2O + Al2S3 -> 3H2S + Al2O3
3H2S + 3C2H5OH -> 3H2O + 3C2H5SH
Or something. Damn! this is another thing I should try myself, but I am pretty much totally without the necessary facilities.
Also, does anyone know exactly what's involved in hydrolysis of nylon? Acids?
And skatole looks very promising, but there still isn't very much information on it. I haven't searched the web very thoroughly, but of the 3800 pages google has I kind of doubt one has a synthesis. It does seem common enough that it's probably at least related to a common chemical.

Draken99
June 3rd, 2004, 08:02 AM
Mercaptanes can be made by reacting alkylbromides with thiourea followed by hydrolysis with NaOH.
(From a german syntesis book)
19g Thiourea, 27ml Bromobutane and 20ml Ethanol are refluxed until a homogenous mixture is formed (approx 5h)
after cooling down to room temperature 25ml of 5M NaOH are added under a stream of Nitrogen or Argon. The Mixture is stirred at 50 - 60°C until no moer oily drops will form a new layer. The layers are separated and the aquous layer is neutralzed with 10% HCl and extracted three times with 30ml ether. the extracts and the organic layer were combined, dries over Na2SO4and distilled(Kp 98°C)

Gretings
Draken

Draken99
June 4th, 2004, 07:00 AM
Hi,
Mercaptanes can be made by reacting Bromoalkanes with Thiourea first and treating the ftemes akkylthiourea with NAOH.
Since it is from a german book I will translate the procedure if requested

Greeting
Draken