soma
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identifying an unknown substance
I have a bottle that used to contain dipropylamine. It has decomposed and now the liquid distills at 95C (dpa bp is 109-111). I would like to find
out what the substance has turned into and am wondering what tests would be used to do that.
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Sigmatropic
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Diisopropyl amine boils at 84 C according to my sources. Perhaps it comes over as a high boiling azeotrope with water? Have you tried distilling over
KOH?
Edit: just read we weren't talking about isopropyl. Sorry. But then again have you dried it prior to distillation?
[Edited on 15-1-2019 by Sigmatropic]
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Tsjerk
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Dipropylamine forms a azeotrope with water at 60 mol% DPA boiling at 86 C. Maybe you have water saturated DPA.
Triethylamine is known to boil at around 75 C when saturated with water, normal bp is 89 C.
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soma
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This should be real dry. There was no way for water to get in other than from the air exposure which was minimal. Also I was distilling it over KOH
and the pot temp was 95. (There was about 150 ml in a lL round bottom.)
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AJKOER
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Photolysis (from a light source, especially UV) or the presence of transition metal impurites and any O2 may lead to a chemical breakdown of the
dipropylamine. Products could include a gas build up, which would be suggestive of this pathway, which leads to an assortment of products.
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