Sciencemadness Discussion Board - How to make 2,4,6 Trichlorophenol?

How to make 2,4,6 Trichlorophenol?

Vlassis - 1-3-2012 at 11:03

Hello Everyone

If someone knows, can you please tell me how to synthesize 2,4,6 Trichlorophenol from phenol.

Thanks in advance

[Edited on 1-3-2012 by Vlassis]

Mailinmypocket - 1-3-2012 at 11:11

You may want to try looking through some of the organic synthesis books found here http://library.sciencemadness.org/library/index.html . I'm not sure off the bat if you will find what you are looking for but worth a try

bbartlog - 1-3-2012 at 12:24

In 'A treatise on chemistry, Volume 3, Part 3' by Henry E Roscoe (1897), he indicates that trichlorophenol is prepared by passing chlorine into phenol, gradually warming it, until the melting point rises to about 67C; at which point it is purified by fractional distillation. I expect such a proceeding would give you a product with substantial impurities in the form of dichlorophenol as well as other isomers of trichlorophenol besides the favored 2,4,6 one.
Other methods include treatment of dilute phenol solution with sodium hypochlorite, and chlorination of solutions of phenol monosulfonic acid, phenol disulfonic acid, or salts of same. See JACS Volume 41 Issue 2 p. 2032. The preparation from phenol monosulfonic acid claims quantitative yields, if that's important to you.

plastics - 1-3-2012 at 12:56

I made sufficient 2,4,6-trichlorophenol ('TCP') to make a decent batch of TCPO by direct chlorination of a solution of phenol. Basic details in 'Fundamental Processes of Dye Chemistry' p146 in the SM library

Phenol is relatively easy to chlorinate to TCP and won't chlorinate further without substantially altering the reaction conditions

A few tips/pointers:

Whilst not possessing an entirely unpleasant odour TCP can be detected at very low concentrations, clings to everything and takes ages (ie days/weeks) to dissipate ie dont spill it on the living room carpet or your clothes

Fill a Dreschel bottle with a solution of phenol acidified with HCl
Bubble in chlorine gas from a chlorine generator (eg action of dilute HCl on TCCA https://www.sciencemadness.org/whisper/viewthread.php?tid=97...)

Ensure you have the wherewithal to generate, react and contain copious quantities of chlorine. I bubbled mine through for 36 hours

Be able to deal with the HCl gas given off as the reaction procedes - this stuff gets the nose worse than chlorine and rots anything metallic in its way

As bbartlog suggests you need to keep the Dreschel bottle warmed above the MP of TCP 69 °C whilst bubbling in the chlorine. If you don't the TCP deposits in the apparatus ultimately clogging the gas delivery tube. I placed my Dreschel bottle in a water bath heated to 75 °C

At the end you will end with a yellow liquid immiscible with water that ultimately solidifies. It can be purified somewhat by recrystallising from acetone in which is exquisitely soluble

Vlassis - 1-3-2012 at 13:33

Thank you all for your replies.

Plastics, I think that I will give it a try with your method.But i have seen the mentioned page on the book, and I could not understand the connection.Can you be a bit more specific about the whole setup, and mention the quantities needed, if that is not much trouble?

BromicAcid - 1-3-2012 at 16:47

Note that trichlorophenol are considered dioxin related wastes/precursors and can be nearly impossible to dispose of legally. It only takes 0.05 ppm to be classified as waste at that point.

plastics - 2-3-2012 at 00:50

Vlassis

I have assumed that you want to synthesise 2,4,6 TCP as a precursor to TCPO and chemiluminescence. If so you might be interested in the following 'greener' approach. I have not tried it yet and it is on a very long list of things to do:

Attachment: GreenChemiLum.pdf (1.3MB)
This file has been downloaded 2401 times

Lambda-Eyde - 2-3-2012 at 03:44

Quote: Originally posted by plastics

I made sufficient 2,4,6-trichlorophenol ('TCP') to make a decent batch of TCPO by direct chlorination of a solution of phenol. Basic details in 'Fundamental Processes of Dye Chemistry' p146 in the SM library

Phenol is relatively easy to chlorinate to TCP and won't chlorinate further without substantially altering the reaction conditions
[...]

No Lewis Acid? Does the chlorination of phenol to 2,4,6-trichlorophenol proceed without a catalyst such as FeCl3 or AlCl3?

Quote: Originally posted by plastics

Vlassis

I have assumed that you want to synthesise 2,4,6 TCP as a precursor to TCPO and chemiluminescence. If so you might be interested in the following 'greener' approach. I have not tried it yet and it is on a very long list of things to do:

Interesting, thank you. However, the perylene they use would be a hindrance for most of us (also, the oxalyl chloride). I have requested some references pertaining to the synthesis of perylene in the References subforum. I have obtained two myself which I have attached (Also, I must say this "green chemistry" is total bullshit - 5 mL DCM in a demonstration experiment won't kill anyone. And who the hell has triacetin in their cupboard anyways? I can understand the desire to replace the TCPO, though.).

Attachment: phpDc4vgB (1.4MB)
This file has been downloaded 875 times

Attachment: Polycondensation of Naphthalene and Its Alkyl Derivatives.pdf (157kB)
This file has been downloaded 805 times

plastics - 2-3-2012 at 04:48

Quote: Originally posted by Lambda-Eyde

No Lewis Acid? Does the chlorination of phenol to 2,4,6-trichlorophenol proceed without a catalyst such as FeCl3 or AlCl3?

The question of a Lewis acid has been addressed before:

http://www.sciencemadness.org/talk/viewthread.php?tid=6757#p...

and I certainly didn't use any in my prep

Quote: Originally posted by Lambda-Eyde

Interesting, thank you. However, the perylene they use would be a hindrance for most of us (also, the oxalyl chloride). I have requested some references pertaining to the synthesis of perylene in the References subforum. I have obtained two myself which I have attached (Also, I must say this "green chemistry" is total bullshit - 5 mL DCM in a demonstration experiment won't kill anyone.And who the hell has triacetin in their cupboard anyways? I can understand the desire to replace the TCPO, though.).

I too am very interested in the potential synthesis of perylene as well as 5,12-naphthacenequinone and its derivatives

I agree with you about the 'green chemistry bullshit' but am interested as it does away with TCP

I'm afraid there does not appear to be an easy way around the use of oxalyl chloride and synthesis of the same has been discussed many times

Vlassis - 2-3-2012 at 05:06

Quote: Originally posted by plastics

Yes I do want to synthesize it for the TCPO but I still cannot understand what exactly I should do(thank you for the greener approach, I might try it out).I hve assignes to my professor at college to find a relatively easy way of making it, but she is still trying.

Dr.Bob - 2-3-2012 at 12:32

Quote: Originally posted by BromicAcid

Note that trichlorophenol are considered dioxin related wastes/precursors and can be nearly impossible to dispose of legally. It only takes 0.05 ppm to be classified as waste at that point.

I would second that note, as the chance of making trace dioxanes as a byproduct are not small, and the legal and health issues of that are not trivial. We did that synthesis in the organic lab that I helped teach years ago, but that was before the crackdown on most chemicals. And making TCP generates a number of related and toxic compounds as well. The 2,4-dinitrophenol esters also work, although they have there own issues, being high energy compounds and precursors.

So the idea of using vanillin as the starting point is great, as that is very easy to obtain, and the oxalyl chloride can be replaced with thionyl chloride as well, although I think oxalyl chloride works better.

I love that area of chemistry, but it has a lot of challenges these days. Luminol is also fun to play with, but requires hydrazine to make, which is another fun challenge.

"However, the perylene they use would be a hindrance for most of us (also, the oxalyl chloride). I have requested some references pertaining to the synthesis of perylene in the References subforum"

The perylene is just a fluorescent dye, so as the paper says, you can use any other fluorescent dye such as "other fluorescers such as rubrene, tetracene, or 9,10-bis(phenylethynyl)anthracene ". They are present in most black light fluroescent paints and dyes.

[Edited on 2-3-2012 by Dr.Bob]

garage chemist - 3-3-2012 at 07:05

Plastics, I am very interested in your synthesis method for 2,4,6-Trichlorophenol. Can you provide a detailed writeup with amounts of phenol, water and HCl used, temperature, chlorination time and setup? I'd like to try this out.

A friend of mine has successfully synthesized perylene and documented the synthesis on a german forum. It's actually not very difficult, though the required chemicals are probably out of reach for most home experimenters.
The synthesis starts with 2-naphthol which is oxidised to 1,1'-bis-(2-naphthol) with FeCl3. The OH groups are then methylated with dimethyl sulfate and the product heated with anhydrous AlCl3 to form 1,12-dihydroxyperylene. This is finally distilled with zinc dust to yield crude perylene.
It was later found and confirmed by someone else that the methylation can be skipped and the bis-naphthol directly reacted with AlCl3 to give dihydroxyperylene.

[Edited on 3-3-2012 by garage chemist]

Hexavalent - 3-3-2012 at 07:45

I would also be interested in the synthesis - it is a nice precursor to TCPO (bis-2,4,6-trichlorophenyloxalate) which is needed to get some homemade glowsticks to work.

plastics - 3-3-2012 at 09:02

Quote: Originally posted by garage chemist

Plastics, I am very interested in your synthesis method for 2,4,6-Trichlorophenol. Can you provide a detailed writeup with amounts of phenol, water and HCl used, temperature, chlorination time and setup? I'd like to try this out.

A friend of mine has successfully synthesized perylene and documented the synthesis on a german forum. It's actually not very difficult, though the required chemicals are probably out of reach for most home experimenters.
The synthesis starts with 2-naphthol which is oxidised to 1,1'-bis-(2-naphthol) with FeCl3. The OH groups are then methylated with dimethyl sulfate and the product heated with anhydrous AlCl3 to form 1,12-dihydroxyperylene. This is finally distilled with zinc dust to yield crude perylene.
It was later found and confirmed by someone else that the methylation can be skipped and the bis-naphthol directly reacted with AlCl3 to give dihydroxyperylene.

[Edited on 3-3-2012 by garage chemist]

garage chemist I feel honored that you are interested in my synthesis. I will dig out the details and publish them in this thread. Do you have a link to the perylene synthesis - this interests me greatly

garage chemist - 3-3-2012 at 10:02

Here's the link: http://forum.lambdasyn.org/index.php/topic,877.0.html

The first step (2-naphthol and FeCl3) looks a bit like black magic on paper. The mechanism is a bit complicated, I can search for it if you like.
As said, the methylation is unneccessary.
There is a nomenclature error in the german text: "2,2´-Dioxy-1,1´-dinaphtyl" is actually 2,2'-dimethoxy-1,1'dinaphthyl, the product of step Nr. 2.
"Dioxy" is obsolete german nomenclature and means "dihydroxy".

Hexavalent - 5-3-2012 at 11:53

Thanks for the link garagechemist, very interesting to read. May try in the future!