arkallic
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tetrahydrofuran synthesis
Hello everyone,
forgive me for I am still a chemistry noobie.
As of recently i've been looking around on tetrahydrofuran synthesis. So I was hoping that maybe someone could help me in understanding how to do it.
If you can that would be absolutely amazing!
Thanks in advance.
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tetrahedron
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just follow these four easy steps:
FURFURAL from corncobs
2-FURANCARBOXYLIC ACID from furfural
FURAN from 2-furancarboxylic acid
TETRAHYDROFURAN from furan
=D
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Nicodem
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Thread Moved
13-11-2012 at 08:29 |
arkallic
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Thank you very much! At first I wasn't too happy about the continuous extraction apparatus but I found an alternative. 
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Poppy
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Thats about the way you go, the last step is the most dificult but corncobs are worth the premisse.
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tetrahedron
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even the first one isn't a joke, i tried once but had a dismal yield. furan is pretty toxic, if you do get there.
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bbartlog
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I'd look at one of the other oxidation-based syntheses that is referenced in Org Syn when doing step 2 (furfural to 2-furancarboxylic acid). The atom
economy of the Cannizzaro is obviously not so good and since the yield is 60% of theoretical (more like 50% if you do the final purification) the
actual molecule-to-molecule yield is more like 25%.
The less you bet, the more you lose when you win.
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arkallic
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I've only seen two so far. The one tetrahedron showed me, and an other one where part of it is where you put furfural and sodium hydroxide in dropping
funnels with a rapid stream of oxygen in more sodium hydroxide in water. and -silver oxide
So I have a few questions. When it comes to the one tetrahedron showed me, must I use a continuous extraction? If so is there a more simple way of
doing things?
and as for the 2nd one, I really dont want to buy a tank of oxygen. Is there a mod that could make it so I don't have to do this? Because i'm finding
that they can be a little pricey. But if I must save up for it... oh well :\ I think I can live with that haha.
Thanks again everyone!
[Edited on 18-11-2012 by arkallic]
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Poppy
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Sorry but, as far as a lazy search was done, can you people explain where the heck is oxygen coming into things in this whole process? Really
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tetrahedron
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2-FUROIC ACID from furfural (2)
| Quote: | | To the flask is added 250 ml. of a 2.5% solution of sodium hydroxide and a cuprous oxide-silver oxide catalyst (Note 2). In the two dropping funnels
are placed, respectively, 96 g. (1.0 mole) of furfural (Note 3) and a solution of 40 g. (1.0 mole) of sodium hydroxide in 100 ml. of water. The
contents of the flask are heated to about 55°, vigorous stirring is started, and a rapid stream of oxygen is bubbled through as the contents of the
two funnels are added simultaneously (Note 4) to the reaction mixture at such a rate (20–25 min.) as to maintain the temperature at 50–55° (Note
5) without external heating. After the additions have been completed, vigorous stirring and passage of oxygen are continued until the temperature
drops below 40° (15–30 min., depending on the rate of oxygen flow). |
maybe a quantitative instead of a catalytic amount of CuO can be used instead.
why are more common oxidants such as peroxide, hypochlorite or dichromate mentioned nowhere?
[Edited on 19-11-2012 by tetrahedron]
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