Furboffle
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diethylamine hcl appearance seems weird
I ordered 100g of diethylamine hcl from some dude in Estonia on ebay. I've had it sitting around since october so like 8-9 months. I looked at the
other day and noticed its turning orange Does diethylamine hcl degrade relatively quickly? or perhaps react with plastic? It came in a ziplock bag
which I've left it in. Its labelled as 99% pure but it being so patchy in color I have my skepticism. is this normal or perhaps I need a better
storage container?
I've dealt with this guy many times and if its something he already has he usually sends it in a baggy or a fancy jar if its something not as stable
or safe, say lithium aluminum hydride. but when its not something he already has he has Sigma drop ship the chemical to me and it cames in their fancy
brand labelled bottle. so based on that I usually just trust the quality of his stuff. I figured being sealed in the bag and kept in a dark storage
box it would be relatively stable plus being in salt form... idk can anyone comment on the appearance?
http://imgur.com/sFz45o7
http://imgur.com/z1gpwnm
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AndersHoveland
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I think I remember reading that dimethylamine does slowly oxidize on exposure to air, gradually taking on a dark brown color in storage, though I
cannot remember what the actual oxidation products were.
I know that oxidation of secondary amines with hydrogen peroxide (particularly in the presence of a tungstate catalyst) results in compounds of the
type R-CH=N(-O)-CH2-R
[Edited on 27-6-2013 by AndersHoveland]
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sonogashira
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It is hygroscopic as the hydrochloride. Wash it with cold absolute EtOH or cold 1:1 dichloroethane/MeOH.
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madscientist
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I'd bet it's trace diethylamine getting oxidized by the atmosphere. Amines tend to cling hard to amine hydrochlorides, as you'll know if you've ever
tried to distill one from the other (it becomes increasingly difficult, approaching impossible). A recrystallization (or wash as sonogarisha
suggested) is in order.
I weep at the sight of flaming acetic anhydride.
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