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  1. #21

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    Quote Originally Posted by Nikola Dulgiarov View Post
    Has anyone actually done this? I have no relevant experience in organic chemistry, besides very rudimentary reactions like nitrations, dehydrations, etc.
    My chemistry teacher is also not too well acquainted
    Red flag red flag red flag. If you can't afford the shipping, can you afford the phone call to Montana? I know even less than you about organic chemistry (though I did somehow pull a "C" in college, and I gather you aren't there yet), but I've talked to Photographer's Formulary about the glycin manufacturing process a number of times and they impressed me on me what an unpleaseant, noxious and obnoxious process it is. They are the only ones who can really give you good advice about the process since they are the only ones doing it. Call them; all we can do is in the way of good advice is "uh...don't do it".

  2. #22

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    I have read "The Methylation of Para-Aminophenol by means of Formaldehyde" by Ernest Carl Wagner, available as a print on demand book, as one does.
    My conclusion was that it would be difficult (and without a lab setup dangerous) even to make Metol from p-aminophenol.
    Though Glycin from p-aminophenol is not discussed it's an interesting read.

  3. #23
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    Ok, I have had the privilege of watching them make Glycin at the Formulary. It is difficult and time consuming. And, it is a good thing that it sits on many acres of land and that there are no problems downwind!

    This is NOT for the home chemist.

    PE

  4. #24
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    Quote Originally Posted by Photo Engineer View Post
    Trichloroacetic Acid is used as an antiseptic by some dermatologists. It is not very toxic except it is good in promoting skin healing after minor surgery.
    A dermatologist knows a lot better how to apply this stuff safely than the bottle you accidently drop on your legs. According to Wikipedia, covering 6% of your skin in Chloroacetic Acid can kill you. Another thing that concerns me in these synthesis steps is the need for boiling Ether in sealed glass tubes. If one of these breaks for whatever reason, you might well have an uncontrolled fuel-air explosive going off right in your lab.
    Trying to be the best of whatever I am, even if what I am is no good.

  5. #25
    Nikola Dulgiarov's Avatar
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    Yes, if the acid is 80% +, there is the risk of acute poisoning. However, a lab coat and gloves are sufficient to prevent problems with spillage, as you can easily take them off before the acid can seep through. Keeping some base to neutralize the acid and a first aid/poisoning kit is a must.
    Boiling ether in a sealed glass tube sounds like the perfect mad-man suicide scenario , although small quantities and a water bath(heated by an induction heater) wouldn't be problematic.
    The key, from what I have seen so far, is to find a salt to bind to the HCl produced during the reaction, yet something that would not react immediately with the monochloroacetic acid. I have found several suggestions, and recommended procedures, temperatures and times. This will remain in the theoretical stage until I am absolutely sure it is safe, and I won't be posting details, so as not to encourage pointless experimentation

  6. #26

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    Quote Originally Posted by Rudeofus View Post
    A dermatologist knows a lot better how to apply this stuff safely than the bottle you accidently drop on your legs. According to Wikipedia, covering 6% of your skin in Chloroacetic Acid can kill you. Another thing that concerns me in these synthesis steps is the need for boiling Ether in sealed glass tubes. If one of these breaks for whatever reason, you might well have an uncontrolled fuel-air explosive going off right in your lab.
    Trichloroacetic Acid and Chloroacetic Acid are very similar in name. But as pointed out earlier do not confuse the two when it comes to how toxic they are. I am a scientist and work in a lab with Trichloroacetic Acid and by the name alone I would have thought that Chloroacetic Acid would be less toxic. That would be wrong. I normally consider the MSDS sheets that come with chemicals to be a joke in that they make everything, including sodium chloride, sound super toxic and dangerious. If this case it would be good to read it.

    Oh and ether explosions. I've been in a lab for one of those. Glad I was on the other side of the large room when it happened. Nobody hurt except the pride of the one who caused it. He thought he knew what he was doing when it happened.

    Just storing a bottle of ether can cause an explosion when the either forms peroxides that are shock sensitive. Sometimes that old bottle of either can explode when you unscrew the lid. That is because the peroxides can form on the underside of the cap. Turning the cap can set them off. If you see any white solid in a bottle of either that has been stored for any amount of time don't open it. Remember sometimes it is under the cap and can't be seen. At least in the USA the more dangerous ethers are stored in metal bottles to lessen the peroxide risk not to make then easier to be seen but because less peroxides from in metal bottles.
    Last edited by brianmquinn; 05-21-2013 at 07:11 AM. Click to view previous post history.

  7. #27
    Nikola Dulgiarov's Avatar
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    Yes, ether is a b*tch to keep, but commercial ether is supplied with stabilizers added, and up to 5% ethyl alcohol greatly lessens the chance of peroxide formation. Nonetheless, it's not something to fool around with, and even I don't store large samples in my lab.
    Now, on to the topic. I have firm reason to believe that the test tube I have with me contains a sample of glycin I only have qualitative tests that may or may not prove to be sufficient to say. What I've done so far is compared paraaminophenol and the sample that I have in the following manner:
    Resistance to oxidation: the same amount of material is dissolved in 10% sodium hydroxide and shaken. The pAP quickly turns purplish to brown, whilst mty sample remains in a clear solution with a yellowish tinge.
    Treatment with an oxidizer: 50% HNO3 quickly oxidizes the pAP, whilst my sample seems less affected, color indication the same as in the above test
    If you have ideas for any other test that can be carried out, I'd be glad to hear you out
    Edit: I also ran a melting point/boiling point test that puts the chemical I have within the range of glycin and also accurately defines its behavior at elevated temperatures, i.e: browns at 200C, begins to melt at 220, completely melted at 247-8, decomp.
    Last edited by Nikola Dulgiarov; 05-21-2013 at 07:57 AM. Click to view previous post history.

  8. #28

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    I have not looked up what the melting point should be but if you have crystals and they melt at the proper temp then I say you have a pure and correct product.

    Another simple test you could do is TLC (if there is a published method)
    Last edited by brianmquinn; 05-21-2013 at 08:35 AM. Click to view previous post history.

  9. #29
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    Yes, please do not confuse chloroacetic acid with trhchloroacetic acid. Two different beasts.

    And be careful in the lab. For those who have seen my lab coat and lab shirt, you know that the coat is NOT good protection. I have holes burned through both of them in the same spot. Also, explosions have a far reach throwing material dozens to hundreds of meters. And fires are rather final as well.

    Take care.

    PE

  10. #30
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    Just to add to the cautions already mentioned, formulae often omit the side-reactions and by-products, which can be toxic, unstable etc., etc., etc., and not suitable for pouring down the drain.
    - Ian

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