DDT, The Pesticide

[inthekitchen]

I apologize if this has already been asked, I searched the forum and found one thread about DDT that mainly talked about Silent Spring, I also checked the Pesticides (http://www.roguesci.org/megalomania/pest.html) section of the Controversial Chem Lab but didn't find anything. A little google searching yeilded some interesting info though.

First, there was DDT's chemical formula and model, obviously really easy to find:

Model:

http://img101.imageshack.us/img101/3443/ddtnh0.gif

Formula: C14H9Cl5

I also dug up an old article from TIME magazine [LINK] (http://www.time.com/time/magazine/article/0,9171,803716,00.html)

The part of the article that caught my eye was this:

...a Swarthmore chemist named Walter Steuber (of Houdry Process Corp.) had decided that the easiest way to get DDT was to make it himself. He was turning it out by the gallon in his cellar. Said Steuber: any competent chemist can figure out the formula and make DDT out of non-priority materials. The ingredients are: chloral hydrate (better known as "Mickey Finn"), monochlor benzine, and concentrated sulfuric acid.

Assuming the above article isn't bullshit, any competent chemist could easily duplicate this Nobel Prize winning chemical with the help of the above information.

But for a confused laymen with only a basic knowledge of chemistry, well--they'd have no way of knowing the proper ratios of chloral hydrate, monochlor benzine, and concentrated sulfuric acid to mix.

On top of that:

Chloral hydrate is now illegal in the US--a substitute would have to be found or a knowledge of how to make chloral hydrate would have to be made.

Sulfuric acid and any kind of chlorinated benzine are also hard to get. I don't think it'd be possible today for "Homemade DDT" to be made like it was back in the 40's.

Am I wrong?

Edit 5-23-08: Dichloro-Diphenyl-Trichloroethane (keyword for searching)

[sirthomasthegreat]

What task are you trying to acomplish? There may be anothe chemical you could use instead of DDT. I will look up on how to make each and what not, but I can do just as good of a job as you with google.

[inthekitchen]

I'm just interested in knowing if DDT can be "homemade" like it was in the 40's, or if there's any kind of "recipe" for it.

[Bugger]

There are many types of chlorinated hydrocarbons that are good insecticides, although most are also poisonous to non-target species in substantial quantities. Solomons' Organic Chemistry has a good description of them, along with their syntheses and biological effects. Others, all of them non-aromatic unlike DDT (1,1,1-trichloro-2,2-bis(p-dichlorophenyl)ethane) and its degradation product DDE, include chlordane, lindane, aldrin, dieldrin, lindane (benzene hexachloride, C6H6Cl12, by adding Cl2 to C6H6 without removal of the Hs), mirex, and kepone. These are all cyclic chlorinated alkanes or alkenes, and, except for DDT and lindane, are all made using hexachlorocyclopentadiene (C5Cl6) via Diels-Alder addition reactions with cyclic alkenes.

Actually, chlorobenzene, used to make DDT, is itself insecticidal. A similar compound, p-dichlorobenzene, is used as a substitute for naphthalene in mothballs, being solid with a vapor pressure and melting point similar to those of naphthalene, unlike chlorobenzene.

Chloral hydrate is CCl3-CH(OH)2. It is used as a sleep-inducing drug, probably via metabolism into chloroform, although its liver-toxicity makes it dangerous on heavy or prolonged use. Being a gem-diol, it is not particularly stable. It is formed on dissolving chloral (trichloroacetaldehyde) in water; chloral can be used in the synthesis of DDT.

The driving-force of the reaction of chloral or its hydrate with two molecules of chlorobenzene is the elimination of two molecules of water between the molecules, catalysed by H2S04 which takes up the water. It seems unlikely that there could be any substitute for the use of choral or its hydrate. A possibility could be to react p-chlorophenol with 1,1,1-trichloroethane, which is a very common solvent used in dry-cleaning and produced in large amounts (as a substitute for CCl4 which is more toxic), again using H2SO4 as catalyst to eliminate molecules of water between the organic molecules; but I have not heard of this being successful.

P.S. SirThomasTheGreat, - what were you knighted for, or are you a Baronet?

[nbk2000]

http://www.versuchschemie.de/topic,6629.html

Complete synthesis. :) Article is in German, so use an online translator and a good imagination. ;)

Also, by further chlorination, you get 2,4-D>2,4,5-T>Dioxin, or at least that's my understanding of it.

Also, a Google book called "The True Story of DDT, PCB, and Dioxin (http://books.google.com/books?id=HOpcT-KtkSwC&dq=ddt+dioxin&printsec=frontcover&source=web&ots=YpNlxBowXb&sig=0ZryXyurWDPYENnyrfpO9i5qfQo)".

Paradichlorobenzene is used as mothballs. Chlorobenzene is a toxic liquid.

[inthekitchen]

http://www.versuchschemie.de/topic,6629.html

Complete synthesis. :) Article is in German, so use an online translator and a good imagination. ;)

Also, by further chlorination, you get 2,4-D>2,4,5-T>Dioxin, or at least that's my understanding of it.
Also, a Google book called "The True Story of DDT, PCB, and Dioxin (http://books.google.com/books?id=HOpcT-KtkSwC&dq=ddt+dioxin&printsec=frontcover&source=web&ots=YpNlxBowXb&sig=0ZryXyurWDPYENnyrfpO9i5qfQo)".

Paradichlorobenzene is used as mothballs. Chlorobenzene is a toxic liquid.

Awe man! This brings me frustratingly close to my goal, but my own limitations have stopped me short, I'm afraid. This full synthesis (Complete with pictures!) is awesome but I don't have the intuitive knowledge of chemistry that I would need to understand the article from the babel fish translation.

I came frustratingly close once again after I did some digging and found the first page of Preparation of Technical DDT (http://pubs.acs.org/cgi-bin/searchRedirect.cgi/iechad/1946/38/i09/f-pdf/f_ie50441a017.pdf) from an old chem journal, I got really excited when I read this:


Typical DDT Concentration

A mixture of 200 grams of 99.0% sulfuric acid, 74 grams (0.5 mole) of chloral purified through the crystalline hydrate, and 124 grams (1.1 moles) of technical chlorobenzene were stirred rapidly...

Unfortunately the rest of the article requires a subscription to The American Chemical Society (http://pubs.acs.org/wls/journals/query/subscriberResults.html?line1=Preparation+of+Techni cal+DDT&op=searchJournals&yearrange4=true&field1=atl%2Ctitle&Submit=Search) which I don't have and can't afford.

The article looked like it was about to give "recipe like" instructions that don't require fancy lab equipment but I could be wrong.

As far as finding a substitute for chloral or chloral hydrate, I guess I can forget that, I'll just assume the stuff is available. In the meantime I wish I could find the rest of that article or a similar article with a "recipe like" process. Poor, uneducated me.

Major Update: Made some more progress: Even though I'm a newbie I was able to find the original patent for the stuff:

DEVTTAIJZING COMPOSITION OF MATTER (http://www.google.com/patents?id=7zRuAAAAEBAJ&printsec=abstract&zoom=4&dq=patent:2329074)


By treating, while strongly stirring, a mixture of 2 molecules of benzene or chlorobenzene with 1 molecule of chloral or chloralhydrate with an excess of concentrated sulfuric acid (of 100 percent strength) heating takes place after same time, which first increases up to about 60 degrees C. and then slowly decreases again. Stirring is continued until the reaction mass has cooled down to room temperature and contains solid particles. Then it is poured into much water whereby the raw condensation product separates out in a solid form. It is well washed out and, after being recrystallized from alcohol, it is obtained in form of white, fine crystals which show a weakly fruit-odor.

Now, being the "blow your fingers off" layman that I am, I probably don't understand the above description the way a chemist would, this is what I think he is saying:

1.Rapidly Stir 2 parts benzene and 1 part chloral with 3 parts sulfuric acid.
2. The mixture should heat up to 60 Degrees C. Stop stirring once the mixture gets back down to room temperature.
3.Pour the mixture into a bucket of water, the ddt should condense out in chunks.

I don't know what it means to "well wash out" or "recrystallize in alcohol"

I know most of the chemists on this forum probably look upon me with contempt, and with good reason, but I'm begging ya for help here!

Am I completely off on the process? What does it mean to "well wash out" and "recrystallize in alcohol" I thought the ddt was already crystallized after being added to the water?

Any advice I'd appreciate!

[nbk2000]

Someone here does have access, so don't be surprised if a copy of that article pops up here soon. :)

[inthekitchen]

Someone here does have access, so don't be surprised if a copy of that article pops up here soon. :)

Explosives and Weapons Forum: 1
University Library: 0

[Enkidu]

Monochlorobenzene sells on eBay for $30 per 500mL. It has a wide range of uses as a solvent, and I do not believe it is a suspicious reagent.

On the other hand, chloral hydrate is not an inconspicuous chemical. You can’t buy it unless you have a license because it’s used as an anesthetic. Chloral hydrate can be made by the chemistry hobbyist. Its synthesis is similar to chloroform, IIRC.

I don’t think your yields will be good (possibly nonexistent, I don’t really know) without oleum. You would certainly need 98% conc. sulfuric acid. With your chemical knowledge, inthekitchen, you can’t make oleum. SO3 is very dangerous. (Actually, you shouldn't do any of this synthesis, noting that you do not even know what molar ratios are.)

If I have time, I will comment more upon this synthesis.

I quickly checked the following excerpt for OCR errors. I believe I caught most of them.

From Vogel’s Practical Organic Chemistry:

The name D.D.T. is derived from dichlorodiphenyltrichloroethane: this is a misnomer since the name represents 27 different compounds. As commonly employed it refers to 2 : 2-bis(p-chlorophenyl)-l : 1 : 1-trichloroethane. It is conveniently prepared by the condensation of chlorobenzene and chloral hydrate in the presence of concentrated sulphuric acid:

[Shows monochlorobenzene + chloral hydrate --> D.D.T. product]

Method 1

In a 1 litre three-necked flask, equipped with a thermometer, glycerine-sealed mechanical stirrer (compare Fig. II, 7, 10) and calcium chloride (or cotton wool) guard tube, introduce successively 700 g. (380 ml.) of concentrated sulphuric acid, 100 g. (53 ml.) of oleum (20 per cent. S03), 90 g. (81-5 ml.) of chlorobenzene and 68 g. of chloral hydrate. Stir the mixture rapidly enough to keep the materials well mixed for 1 hour: during this period the temperature rises to about 50° and some granular D.D.T. separates. Stir the mixture for a further 1 hour in order to complete the reaction. Pour the reaction mixture with stirring into 3 litres of a 2 : 1 mixture of ice and water. Filter the precipitated somewhat sticky solid at the pump and wash it well with cold water. Remove the occluded acid by transferring the crude product to a beaker containing 1 litre of boiling water and stirring well: this causes the D.D.T. to melt. Decant the aqueous layer, and repeat the washing with two further 1-litre portions of water. To the third washing add a little sodium bicarbonate and stir until the mixture is neutral to litmus. Filter at the pump, and dry upon filter paper in the air or in an air oven at 50-60°. The yield of crude product, m.p. ca. 90°, is 90 g.; the low m.p. is due to the presence of isomers of the para compound. The pure substance, m.p. 108°, may be obtained with 50-60 per cent, recovery by recrystallization from n-propyl alcohol (5 ml. per gram).

Method 2

Place 17 g. of chloral hydrate crystals and 25.5 g. (23 ml.) of chlorobenzene in a 500 ml. Pyrex glass-stoppered reagent bottle and warm on a water bath, with occasional shaking, until all the crystals have dissolved. Cool to room temperature and slowly add 180 ml. of concentrated sulphuric acid. Secure the glass stopper (rubber tubing over stopper held tightly by copper wire round neck of bottle) and shake mechanically for 1 to 1 -5 hours, and then allow to stand for 15 minutes. Pour the contents of the reagent bottle slowly and with constant stirring into 700 ml. of water contained in a litre beaker. When cold, filter the crude D.D.T. through a sintered glass funnel and wash several times with water. (A further 1 -5 g. of impure D.D.T. may be obtained by diluting the filtrate considerably.) Transfer the solid to a beaker and stir it for 5-10 minutes with 50 ml. of 2 per cent, sodium carbonate solution or 4 per cent, sodium bicarbonate solution. Filter and wash with distilled water until the filtrate is neutral to litmus; suck the solid as dry as possible. Transfer the residue to a small mortar, add 100 ml. of ethyl alcohol and triturate with a pestle for 5-10 minutes. Filter through a dry Buchner funnel, wash twice with 25 ml. portions of ethanol, and continue the suction until most of the solvent has been removed. Dry the residue at 70° in a steam oven (or on a water bath). The yield of D.D.T., m.p. 107°, is 15 g. The perfectly pure compound, m.p. 108°, may be obtained by recrystallization from n-propyl alcohol (5 ml. per gram).

[inthekitchen]

Drat, are there no easier to obtain pesticides that match ddt's effectiveness? Well, looks like the obstacles remaining include:

1.Obtaining choral hydrate
2.Obtaining all the lab equipment (Vacuum pumps, filter funnels, etc. awfully pricey probably run near $100 bucks, and I wouldn't use it that often)
3.Obtaining ethanol, unless using "denatured ethanol" at 75% is not a problem.
4. Obtaining a mechanical shaker (500 dollars and up, unless I made one)

I guess when they say ddt is cheap and easy to make they mean from the perspective of an industrial chemist.

[Alexires]

*whistle* Hang on there inthekitchen.

Here is a little high school chem for you. It will make your life ALOT easier if you can get your mind around it.

Lets start with a nice simple equation and work from there (I'm not being patronizing).

HCl + NaOH->NaCl + H2O

You get that right? You add some acid (hydrochloric acid) to some base (sodium hydroxide) and you get a salt (sodium chloride - table salt) and some water.

If you think about it this way now

1(HCl) + 1(NaOH) -> 1(NaCl) + 1(H2O)

So, we know that one molecule of HCl reacts with 1 molecule of NaOH to form 1 molecule of NaCl and 1 molecule of H2O. Normally when we write chemical equations, we just get rid of the ones and assume they are ones unless stated otherwise.

But the problem is, how many HCl molecules are there in your 10mL test tube?

We know that every element has its own "mass" which we call the "molecular mass" or "atomic mass". For instance, if you look at any decent periodic table, somewhere in each element square you will see some numbers designated as the "atomic mass". Hydrogen is roughly 1.008, Carbon = 12.011, Oxygen = 15.9994 etc. You should be able to find the number I'm talking about.

Now, here comes the mind bending bit. If you have 12.011g of Carbon, you will have 6.023x1023 atoms of carbon. If you have 1.008g of hydrogen, you have 6.023x1023 atoms of hydrogen. If you have 15.9994g of Oxygen, you have 6.023x1023 atoms of oxygen.

See the pattern?

But, I can hear you screaming, how does this help? Well, the same theory applies for different compounds. If we go back to our example of HCl + NaOH, we can now say this.

We know that HCl has a total atomic mass given by atomic mass of Hydrogen + the atomic mass of Chlorine. 1 atom of hydrogen is bonded with 1 atom of chlorine

Or, in otherwords 1.008+35.45= 36.458. This is the atomic mass of a HCl molecule. If we relate this back to 6.023x1023 (otherwise known as Avogadro's Number), we know that in 36.458g of PURE HCl there is 6.023x1023 molecules of HCl.

If we now run it for NaOH, we know that its atomic mass is 39.9974 (22.99+15.9994+1.008) so that if we have 39.9974g of PURE NaOH, there is also 6.023x1023 molecules of NaOH. We can also say that there is one MOLE of NaOH or HCl (because there is 6.023x1023 molecules of each)

Hence, if you wanted to completely neutralise 1 mole of NaOH (which weighs 39.9974g) you would add 1 mole of HCl (which weighs 36.458g)

Get what is happening so far?

Now, if we relate this back to the article that you posted here, we see that it says

By treating, while strongly stirring, a mixture of 2 molecules of benzene or chlorobenzene with 1 molecule of chloral or chloralhydrate with an excess of concentrated sulfuric acid (of 100 percent strength) heating takes place after same time, which first increases up to about 60 degrees C. and then slowly decreases again.

Ok, so 1 molecule of Chloral (CCl3CHO) is reacted with 2 molecules of Benzene or chlorobenzene (C6H6 or C6H5Cl respectively). We since we know how much of each element there is in in both chloral and either benzene of chlorobenzene, we can work out its atomic weight.

I'm just going to use Benzene and Chloral, cause that will make it easier.

So, we now know that Benzene has at atomic weight of (6x12.011)+(6x1.008) or 78.114, and chloral has an atomic weight of 147.38. So, finally, we work out that for every 156.23g of benzene (or two moles), we need 147.38g of chloral (which is one mole) for it to react in a 2:1 MOLAR ratio.

Sounds strange huh?

It takes a while to get your head around.

I only took the time to tell you this because you look like you actually want to learn something and aren't just a kewl looking for some spoonfeeding.

If you have any difficulties, PM and I'll help you as best I can.

Anyone see a problem with my explaination, go ahead and say something.

Also, note inthekitchen, that the % of acids correspond to how many HCl or HNO3, etc molecules are in there in relation to the water. PURE HCl is actually a gas, and will dissolve into water, but the maximum HCl acid you get is about 33% I think. So, if you needed 10g of PURE HCl, then you would need 30g of your 33% acid, or there about.

Edit: Just read your latest post inthekitchen. If you can buy the vacuum gear and you plan to continue with this hobby BUY IT. Vacuum pumps, vacuum traps and reduced pressure gear is GREAT to have.

Why obtain Chloral or Chloral Hydrate? Make it. If you have vacuum gear, you can make almost ANYTHING. Same deal with the ethanol. Get your vodka or whatever you are using, toss it into the vacuum flasks with some sulfuric and distill off the ethanol.

Improvise my friend. You have a drier? A washing machine? Make something that holds your container you want to shake and attach it (temporarily) to the drier/washing machine while it is running. The shuddering while it is on spin cycle will shake it. You don't need to fork out money, you just need to think about it abit.

[inthekitchen]

Your explanation made perfect sense, with some fervent references to a periodic table and a working calculator I should be able to determine the necessary amounts to meet the proper molar ratios.

I was thinking of just giving up and seeing if any of the stuff was still for sale. There is a farmer selling some ddt but he is selling it for over 500 dollars a pound! I'm assuming its stuff left over from the pre-ban days.

I guess my only option is to buy the equipment and use my dryer as a shaker (or I could tape a vibrator to a wooden plank and a slinky, that would be more cost effective).

Anybody know a landlocked (not online) store I could pick up glass supplies, like a chain or a specific type of store I should look for in the yellow pages?


In the meantime I'm off to read Process of Manufacturing Chloral (http://www.google.com/patents?id=IfhFAAAAEBAJ&printsec=abstract&zoom=4&dq=chloral)

[nbk2000]

Acronyms are usually capitalized, so it's DDT, not ddt. ;)

Making chloral isn't too terribly difficult to do, as you simply pass dry chlorine gas through anhydrous ethanol, slowly warming it up to reflux, so as to replace some of the hydrogen in the ethanol with chlorine.

You can find the process (copied from Dick's) in the PMJB, Vol 1.

[megalomania]

I have had several methods of making DDT lying around here for a few years now; I guess it is about time I actually added the info to my website. I love pesticides and herbicides precisely because everyone else hates them :)

[Bugger]

You say you have "several methods of making DDT lying around". Besides the well-known one involving chlorobenzene and chloral, do any of the other methods include reacting p-chlorophenol with 1,1,1-trichloroethane (a very common solvent used in dry-cleaning and produced in large amounts as a substitute for CCl4 which is more toxic), again using H2SO4 as catalyst to eliminate molecules of water between the organic molecules, as I suggested as another possibility above? Has anyone tried this?

[megalomania]

I don't rightly know because I have misplaced the folder that contains the references. I know that it is in my brown leather folder, I remember putting my CW information there, but for the life of me I can't find it.

I am in the midst of putting all of my files into a filing cabinet I purchased into distinct folders by compound. What prompted this is a massive stack of journals I requested that I have no god damn idea why (it is not obvious what compound of interest I wanted from the article)! As of now many files are lumped into bins and folders. I have not prioritized the CW info very high, so it is still disorganized.

In short, bugger, I can't answer your question...

[Enkidu]

Do any of the other methods include reacting p-chlorophenol with 1,1,1-trichloroethane, again using H2SO4 as catalyst to eliminate molecules of water between the organic molecules, as I suggested as another possibility above? Has anyone tried this?

I'm sorry Bugger, but I don't think this idea works. Do you have a reference for it or is it something you came up with? If you have a reference, please post it; otherwise, please explain your reasoning. For a long time I didn't know how to begin to understand what you proposed. This lack prevented me from responding to your idea.

Unfortunately, I believe the best you could hope for would be 4-chloro-3,5-sulfonicphenol dissolved by trichloroethane. You can't remove the -OH from a benzene ring easily. Even if you could, the best you could hope for would be di(4-chlorophenyl) ether through the Williamson Ether Synthesis.

I will explain the current method of production of DDT. As I have never seen anyone else’s mechanism for this reaction, my explanation is only as good as your faith in my knowledge of chemistry.

In an extremely concentrated, acidic solution, H2O becomes a good leaving group. Take, for example, chloral hydrate. The H2SO4 protonates the –OH on the 1 carbon, and the –OH2+ leaves (and becomes regular water), creating a carbocation. (A carbocation is a positively charged carbon atom. A carbocation has only three bonds, instead of the desired four.) The H2O is immediately eaten by the SO3, which produces another molecule of H2SO4.

The formation of the carbocation is in preparation for the electrophilic aromatic substitution of the p-chlorobenzene. Chlorine (or any halogen) is an ortho / para deactivator, so the substitution will occur at para (4) position, respective to the Cl. The pi bond on the benzene ring jumps out and attacks the carbocation. The 3 carbon on the benzene ring is now positive. The HSO4- pulls off the hydrogen on the 4 carbon, and the electrons from the carbon-hydrogen bond reform the pi bond.

A nitration is another instance of electrophilic aromatic substitution. It uses the nitronium ion (NO2+).

The second chlorophenyl group is attached in the same manner.

Another (just as likely) mechanism involves the chloral hydrate being turned into chloral first. Its mechanism is similar to what I’ve just written.

[inthekitchen]

Quick Question Enkidu, do you have the page number for that ddt synthesis in vogel's? I got a'hold of the 5th edition but can't seem to locate it in the index? Are you using an older version?

[Enkidu]

@inthekitchen: It's on page 1011 of Vogel's Practical Organic Chemistry, 3rd ed. I don't think the 5th ed. contains the synthesis.

[junk12]

Alexires, very nice post. I appreciate an effort. For some of us, who are members of this forum and our first profession isn't chemistry related, here and there is useful to recall some of high school chemistry that was forgotten.

[Enkidu]

Preparation of Technical DDT.
H. S. Mosher, M. R. Cannon, E. A. Conroy, R. E. Van Strien, D. P. Spalding
Ind. Eng. Chem.; 1946; 38(9); 916-923. DOI: 10.1021/ie50441a017


Apparently the upload feature isn't working for me. I'll upload the article later if somebody reminds me (or I remember).

[russoc4]

Here's a copy of that article. Not the best quality scan. This is the first time I've seen a poorly scanned ACS article, though:

http://rapidshare.com/files/117166131/ddt_synthesis.pdf.html

Maybe these patents will shed some light on chloral (or not)

http://www.google.com/patents?id=Q11vAAAAEBAJ&dq=2615049
http://www.google.com/patents?id=0lFPAAAAEBAJ&dq=2702303