Jor
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acetylacetone / penta-2,4-dione
I have used the search engine, using different names for the compound. I didnt find a synthesis yet.
Acetic anhydride is reacted with acetone to form acetylacetone. The reaction is BF3 catalysed. Now Ac2O and acetone are both readily available to me,
but the BF3 is very expensive and dangerous. I want to prepare some acetylacetone, because this chemical is very expensive. I only need at most 50mL,
for the use as an complexing agent.
Now , would there be an alternative if BF3 is not available? Is BF3 just there to speed the reaction up, or doesnt it proceed at all without this
catalyst. If it is there, just to speed things up, I would be able to react acetone and Ac2O for a long time, say days.
Ideas?
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Nicodem
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Please put references for the discussed methods! It is unpleasant to search for what you are talking about, when it would be in your interest to
provide this link to that BF3 catalyzed method: http://www.orgsynth.com/orgsyn/prep.asp?prep=cv3p0016
Also, doing so, some member could have easily pointed you out that you did not check the alternative syntheses provided therein:
Quote: | 3. Discussion
Acetylacetone has been prepared by the reaction of acetyl chloride with aluminum chloride, followed by hydrolysis;3 by the condensation of acetone
with ethyl acetate in the presence of sodium,4 sodium amide,5,6 sodium ethoxide,5,7,8 and alkali or alkaline-earth hydrides;9 by the reaction of
acetone and acetic anhydride in the presence of boron trifluoride;10 by the pyrolysis of isopropenyl acetate;11,12,13 by the reaction of ethyl
acetoacetate and acetic anhydride in the presence of magnesium at 140°;11 from methyl or ethyl diacetylacetate by treatment with acids;14 and by the
dehydrogenation of 4-pentanol-2-one in the presence of Raney nickel.15
References and Notes
1. Bagster, J. Chem. Soc., 1917, 494.
2. Obermiller and Goertz, Z. physik. Chem., 109, 162 (1924)
3. Combes, Ann. chim. et phys., (6) 12, 207 (1887).
4. Claisen, Ann., 277, 168 (1893).
5. Claisen, Ber., 38, 695 (1905).
6. Adams and Hauser, J. Am. Chem. Soc., 66, 1220 (1944).
7. Claisen and Ehrhardt, Ber., 22, 1010 (1889).
8. Sprague, Beckham, and Adkins, J. Am. Chem. Soc., 56, 2665 (1934).
9. U. S. pat. 2,158,071 [C. A., 33, 6342 (1939)].
10. Meerwein and Vossen, J. prakt. Chem., 141, 149 (1934).
11. U. S. pat. 2,395,800 [C. A., 40, 3130 (1946)].
12. Brit. pat. 615,523 [C. A., 43, 7954 (1949)].
13. Hagemeyer and Hull, Ind. Eng. Chem., 41, 2920 (1949).
14. U. S. pat. 2,395,012 [C. A., 40, 3130 (1946)].
15. DuBois, Compt. rend., 224, 1734 (1947).
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For the preparation from ethyl acetate and acetone, see also:
US6410795;
Journal of Industrial and Engineering Chemistry (Washington, D. C.), 49 (1957) 1067-1070;
...and others.
PS: Are you sure you checked the prices correctly? Acetylacetone is very cheap, in fact it is even cheaper than acetanhydride and you don't have to
sign any end user papers for it.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Jor
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I don't have the password for References. Well I had, but I think it has changed, because it doesn't work anymore for me.
I totally forgot searching on orgsyn. That is really stupid. Im very sorry. I got my synth. from wiki.
Thanks anyway for the patent.
I have checked many hobby suppliers, and they don't sell it. When I check Fisher, the cheapest I can have is 500mL for 100,00....
I dont know yet about Baker or Acros, prices must be requested, but I think they are not really much cheaper than Fisher.
Acetic Anhydride is very cheap for me. 15,00 EUR for a liter.
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MagicJigPipe
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Do you mean $100,000 or $10,000!? My god man either way that is insane.
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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woelen
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Labthings on eBay sells acetylacetone. I have seen it listed a few times, but never cared about it. You could try mailing her or sending an eBay
message to her.
!!! Don't mess around with BF3-ether complex, given the facilities you have right now. This is an hydrolizable fluorine compound, which is not
something to think about lightly. I would place it in the same area of risk as HF.
100,00 in Dutch notation equals 100.00 in US-notation. So, he is talking about 100 euros, not 10000 or 100000
[Edited on 18-3-08 by woelen]
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