Athiril
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Derivatives of p-phenylene diamine?
There are PPD in many products everywhere.. dyes, inks to name a few, is it hard to extract and purify?
My main question is on production of PPD derivatives from straight PPD.
For example, I have
CD-2 in dry crystal form (4-(N,N-Diethyl)-2-methyl-p-phenylenediamine monohydrochloride)
http://www.chemblink.com/products/2051-79-8.htm
And CD-3 and CD-4 in acid solutions from Kodak that are part of film developing kits.
What I'd like to do is begin putting knowledge together of getting from PPD, to these 3 products.
Obviously I don't expect to do this overnight or even this year.
But I don't know where to begin, and want to put together research and notes to get there eventually, so any pointers in the right direction would be
appreciated.
CD-4 is
4-(N-Ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine sulfate
http://www.chemblink.com/products/25646-77-9.htm
CD-3 is
4-(N-Ethyl-N-2-methanesulfonylaminoethyl)-2-methylphenylenediamine sulfate
http://www.chemblink.com/products/24567-76-8.htm
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Nicodem
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p-Phenylenediamine is not a good starting material for those targets. Is there a particular reason why you chose those compounds for synthesis? If
not, I suggest you to use your phenylenediamine for some other syntheses.
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Athiril
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Yes, I'm not looking for something to do with p-phenylene diamine, I'm looking for ways to get to those compounds.
Okay, what would be a good starting compound?
CD-3, and CD-4 produce the correct dyes for E-6 film (CD-3) and C-41 film (CD-4), using a different ppd agent gives different organic dyes which are
not stable. I want them for a future practical use, I could get them in from China or India in bulk, but well preserving the knowledge is good.
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Nicodem
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Maybe it would be best if you first review the scientific literature and patents to see how it is best done in a simple and economic way. Given that
you don't have enough knowledge to develop a synthesis, you are pretty much limited to the existing processes, which is usually only of advantage when
your goal is to make something rather than to invent something.
I assume most syntheses start with m-toluidine or o-toluidine, but it would still be a multistep synthesis requiring many reagents of which at least
one (ethylene oxide) is carcinogenic. Additionally, you would first have to do some practice with pedagogic experiments to acquire general synthetic
organic lab skills prior to embark on such a project. Members here generally don't just jump into such relatively demanding projects without years of
expertise (at least not serious members - not taking into account kewls and their mental masturbations). If you still want to go ahead, I'm sure there
are many of us who will be willing to assist you, but first do a literature search like suggested. If you don't know how to do this - I assume you
don't have access to Chemical Abstracts / SciFinder or Beilstein / Reaxys - someone will help you out later, but I don't want to ruin you the fun of
attempting by yourself first.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Athiril
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I'm not attempting to do this overnight, this is a long term project. There are many carcinogenic compounds in some analogue photography workflows -
such as formaldehyde in solution which I have to deal with on a nearly daily basis.
I haven't heard of the things you mentioned, but I have read up on some patents before for other things on general patent websites, I usually find
them hard to digest even if the information is simple, due to the repetition and vagueness of many of them, and having to find the needle in the hay
stack.
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Nicodem
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I don't think you understood. Ethylene oxide is no piece of cake like formaldehyde. It is one of those serious carcinogens and a highly toxic gas that
can kill you in a few breaths.
SciFinder gives 54 references (patents and sci. literature) associated with the preparation or process for making CD-4. You can find these references
in the attachment. The seminal article that you need to read first of them all is J. Am. Chem. Soc., 1951, 73, 3100–3125 (DOI: 10.1021/ja01151a037),
which also contains syntheses of relates photography chemicals. Most patents are the old Japonese ones with few European national and some EP patents.
Most if not all process development, which is what you need most, is described in the articles published in some Chinese scientific journals.
As far as I can see from the literature and just like I assumed, practically all make CD-4 via m-toluidine -> N-ethyl-m-toluidine ->
N-ethyl-N-(2-hydroxyethyl)-m-toluidine -> N-ethyl-N-(2-hydroxyethyl)-3-methyl-4-nitrosoaniline -> CD-4. Variations are only in the methodologies
used.
The last two steps are commonly nitrosation followed by hydrogenation over Pd-C (with NaNO2/HCl as in Xiandai Huagong (2000) 20, 44-45 or with
isopropyl nitrite as in EP621260). The hydroxyethylation generally requires the use of ethylene oxide and most patents use it in an autoclave or in
combination with an acid catalyst. The cited Xiandai Huagong article, as well as Huaxue Shiji (1993) 15, 383, both describe also the use of in situ
generated ethylene oxide made from 2-chloroethanol, which is certainly a much safer alternative though still not safe. N-Ethyl-m-toluidine can be made
using numerous procedures, including also the direct N-ethylation with ethyl iodide.
Edit: Forgot the attachment.
Attachment: CD-4 SciFinder output.pdf (143kB)
This file has been downloaded 751 times
[Edited on 4/9/2011 by Nicodem]
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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