Pickardjr
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esterfication
Hello and greetings everyone . I am trying a quite simple reaction of glycerin 20ml , 5 % clear vinegar 25ml , con. sulfuric acid ( estimated 98%
purity) 3-4 drops. This mixture will be heated @
77 C for 7-8 hrs, thus reducing the volume hopefully by half. May not have to go that long though.
Them con. ammonium hydroxide added to try aminolysis of the ester to produce acetamide.
I've never made an ester before but have a book with instruction for similar esterfication. The ester and ammonia would be mixed for 1 week or so.
I'd like some thoughts on this. I'm just trying to prove viability of reaction so yield at this point is not priority .
[Edited on 27-2-2014 by Pickardjr]
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DraconicAcid
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Vinegar's not going to work for forming an ester- too much water in it.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Pickardjr
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I believe it did produce a infinitesimal amount due to smell of acetate, however I call this a fail. Will try later w/ acetic acid.
[Edited on 27-2-2014 by Pickardjr]
[Edited on 27-2-2014 by Pickardjr]
[Edited on 27-2-2014 by Pickardjr]
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AvBaeyer
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Why are you choosing to use glycerine as the alcohol for your esterification? That appears to be a strange choice based on what you seem to want to
do, simply make an ester. Why not try using isopropanol as the alcohol and esterify with glacial acetic acid and catalytic H2SO4? You should be able
to easily find 99% isopropanol which will work pretty well (70% and 91% will not be good choices as they have too much water in them). Where I live
99% is available at Safeway.
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mnick12
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As others mentioned, vinegar will not work. similarly glycerin is a weird choice especially if you trying to make acetamide, ethyl acetate is much
easier to get a hold of. If you do have AcOH and dry glycerin and are intent on making the triacetate, a dean-stark apparatus might work to shift the
equilibrium in your favor. I would use a large excess of acetic acid then distillation.
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DraconicAcid
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Quote: Originally posted by Pickardjr  | | I believe it did produce a infinitesimal amount due to smell of acetate, however I call this a fail. Will try later w/ acetic acid.
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Smell of what acetate? I know what ethyl acetate smells like, but I would expect glycerine triacetate would smell completely different.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Panache
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Use citric acid and ethanol with the sulphuric
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Pickardjr
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Ok , I want to thank everyone for all the great input, great positive energy. I will explain my intentions briefly. I first wanted to try and form
this glycerin triacetate from house hold items very easily to find, yea I know I can get GAA and alot more. However that was not in the experiment,
(household) Vinegar was just that.
In any event what I want to work on was to use glycerine to form an ester with other natural carboxylic acids, say like amino acids. Then in the same
reaction system add a anhydrous secondary amine, seal the mixture in a small round bottom flask and gently and evenly heat in an oil bath. I haven't
worked all the details out yet.
My hope would be that the ester would react with the amine (aminolysis) and produce the amide. This is a viable route and patented method for amides.
Can be applied to many different amines and esters/carboxylic acids, to what degree is debatable. Still in research mode.
[Edited on 28-2-2014 by Pickardjr]
[Edited on 28-2-2014 by Pickardjr] It smelled alot like ethylacetate Except that it was a cross between a(winter greenish) smell with ethyl acetate
and was different than glycerine too. The whole room smelled of ester. You ever been in a lab that students were making butyl acetate, you can smell
it down the hall. It was kind ester-ish smell. So there you go thats what it smelled like.
[Edited on 28-2-2014 by Pickardjr]
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Nicodem
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Thread Moved
1-3-2014 at 11:04 |
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