Nickbb
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Salicylic acid solution turning pink
Hello, I was recrystallizing salicylic acid I synthesized recently using hardware grade acetone to dissolve it. Everything has been going normal, but
today it is suddenly pink. Where did that come from? Is it possible that iron laying around could of somehow contaminated it?
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Adas
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I know that phenol oxidizes slowly on air to create pink color, don't know if that's true for Salicylic Acid.
Rest In Pieces!
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Urzah
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I got the same while synthetizing acetylsalicylic acid, on the recristallization phase. It was a missed operation, so I think I had almost only
salicylic acid too....
Dont know why it turned pink. Thought it was some impurity, but if it happens often with multiple chemists, it is something more. Maybe a sub-reaction
with something? Quality of ethanol? Dont know....
If it happens once more, I'll note every steps I'll do.
(sorry for the syntax and orthograph. English is my second language)
Urz
Edit: corrected mistypes
[Edited on 6-2-2013 by Urzah]
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bfesser
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I once had a suspension of acetylsalicylic acid in water turn pink upon sitting for a few days.
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Vargouille
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I can remember from other posts that they had solutions of acetylsalicylate oxidize to a pink solution. Analogously, it is known that solutions of
sodium cyclopentadienide go to pink, violet, and eventually brown upon aerial oxidation. Likely a similar process going on here.
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smaerd
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I've been trying to find out the mechanism for phenol or phenolate oxidations for a long time with no luck. I was wondering if anyone had any links or
articles?
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demiurgent
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Quote: Originally posted by smaerd  | | I've been trying to find out the mechanism for phenol or phenolate oxidations for a long time with no luck. I was wondering if anyone had any links or
articles? |
http://pubs.acs.org/doi/abs/10.1021/i100016a002
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Nickbb
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Thanks for the responses. I've collected the crystals and decided to keep the pink solution left over that is highly saturated with salicylic acid.
I'll let that dry out and see what happens. The crystals I have are nice a pure looking.
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Nickbb
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What compound is this?
I recently took some of the salicylic acid and put it in a testtube and heated it with a flame. It quickly melted and turned into a very dark pink
color. The result was soluble in acetone and made a brownish solution. I evaporated that and it left a brownish powder and had a 'plastic' like smell.
Does anyone have any idea what this actually is?
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