Aikimike
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1,3 Acetonedicarboxylic Acid
Hello all,
I have some Glutamic Acid and find myself in need of 1,3 Acetonedicarboxylic Acid. All I need to do is to remove the amino group, add a Hydroxy group
and then oxidise the Hydroxy to a Carbonyl.
Sounds easy but as Im just starting advanced chem, I really am not too sure as to how I can go about doing this. If anyone can offer any advice as to
how this may be acomplished it would be very much appreciated.
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Sauron
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You are going the wrong way round the block and probably, will get lost.
Rather than trying to find a bew way to make acetonedicarboxylic acid, why not take the path of least resistance?
Buy ANHYDROUS citric acid. OUTSIDE or in a good fume hood, treat this with 20% oleum (fuming sulfuric acid.) All the details are available online in
Org.Syn.
This reaction gives off lots of carbon monoxide, which is why you should only do it outside or in a good hood. Otherwise = death.
You work up the acetonedicarboxylic acid as its diethyl ester and recrystallize that from ethyl acetate to purify. The free acid is not very stable.
Better to store it as the diester unless you want to use it right away.
Sic gorgeamus a los subjectatus nunc.
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Aikimike
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As much as the Oleum route is a much easier way to go, I had a distinct desire to avoid using Oleum (horribly toxic, fumes SO3 etc. etc.) So was
wondering whether this method would be feasible.
Also I believe that there was a refernce posted on here about the use of Hot Sulphuric Acid (not fuming) which I tried- this however proved less than
fruitful because there was no easy way in which to filter the product from the Sulphuric Acid as H2SO4+ filter paper= no more filter paper.
If there is any way in which the previously stated synthesis could work, advice would be much appreciated.
Thank you very much Sauron for your swift response!
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bfesser
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Try using a fritted glass filter funnel or buying glass microfiber filters instead of using cellulose paper.
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chemoleo
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I thought something wasn't right:
Check glutamic acid:
Now check acetonedicarboxylic acid:
The NH2 is not in the correct position, you'd be making alpha ketoglutaric acid, a well-known biochemical metabolic product in the citric acid cycle:
[Edited on 16-8-2008 by chemoleo]
Never Stop to Begin, and Never Begin to Stop...
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Sauron
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It is possible to get acetonedicarboxylic acid from anhydrous citric acid and conc H2SO4 rather than oleum, but the yields are poor and you still have
all that CO to deal with. It is the CO effluent and not the SO3 (which is only within the reaction flask) that you have to worry about.
Sic gorgeamus a los subjectatus nunc.
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Aikimike
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Hmm, I see:
If I were to conduct a mild oxidation of glycerol with Hydrogen Peroxide and A ferrous salt as catalyst (Idea from Wiki: http://en.wikipedia.org/wiki/Dihydroxyacetone) to make Dihydroxyacetone and glyceraldehyde firstly how could I separate the products and secondly,
would it be reasonable to assume that carboxylation would take place with formic acid? Or perhaps chlorination with Thionyl chloride and then
treatment with formic acid to yield the desired product?
Thanks for your time.
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Sauron
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Procedures with DHA and glyceraldehyde look fine on paper but are usually a nightmare in reality.
Citric acid is cheap. So is conc H2SO4. So, to hell with the low yield, go this route and accumulate as much ADCA as you need. Remember, it won't keep
except as the diester, or the anhydride (if you have acetic anhydride around.)
Otherwise acetonedicarboxylic acid just turns into acetone and CO2.
Sic gorgeamus a los subjectatus nunc.
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Nicodem
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| Quote: | Originally posted by Aikimike
Hmm, I see:
If I were to conduct a mild oxidation of glycerol with Hydrogen Peroxide and A ferrous salt as catalyst (Idea from Wiki: http://en.wikipedia.org/wiki/Dihydroxyacetone) to make Dihydroxyacetone and glyceraldehyde firstly how could I separate the products and secondly,
would it be reasonable to assume that carboxylation would take place with formic acid? Or perhaps chlorination with Thionyl chloride and then
treatment with formic acid to yield the desired product?
Thanks for your time. |
It appears to me you lack some basic knowledge of organic chemistry. Try reading some books on basic organic chemistry and then some describing the
reaction mechanisms. I know this can take years, but trust me, it will help you a lot to know the theory when doing experiments. The worst thing when
working in the lab is not so much the poor practical skills, but not knowing what is going on in the reaction flask. This lack of knowledge can kill
when doing experiments on larger scale. Once you have the basic knowledge you can start with experiments on a 10 mmol scale and if everything goes
well increase the reaction scale.
Poor man's oleum can be made by mixing sodium pyrosulfate with conc. sulfuric acid and decanting from the resulting Na2SO4. There is at least one
patent describing the process (and probably something on this forum as well).
Sodium pyrosulfate (Na2S2O7) can be prepared by heating the NaHSO4 monohydrate melt (can be bought in just about any larger supermarket) till correct
weight drop (-1.5 H2O). You can do this on a hot plate in a stainless steel vessel (which will corrode a bit tainting the product green, but not
much). Alternatively, you can thermolyse sodium persulfate like Garage_chemist did: http://www.sciencemadness.org/member_publications/SO3_and_ol...
Citric acid monohydrate can be bought in the supermarkets or pharmacies. The process for its dehydration is relatively easy and is quite probably also
described somewhere on this forum.
…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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ScienceSquirrel
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I have had a look at some of your previous posts and I would ask how many previous organic chemistry experiments have you performed on your own?
While I would not wish to discourage you in any way, I would question if an experiment that involves oleum and produces carbon monoxide as a byproduct
is one to include in your first 50 or even 100 experiments if you are doing them on your own without a more experienced 'mentor' to keep an eye on
things.
Experimental chemistry is as much an art as a science and even very experienced chemists have 'leg it' moments
If you have not already made some benzamide, iodoform, methyl salicylate etc may I suggest you try those first.
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Nicodem
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I don't think the synthesis of acetonedicarboxylic acid is impossible for beginners. I think he should try it out, but with all due precautions and on
a small scale (doing a 10mmol reaction outside represents no danger from CO poisoning). Even though it is quite likely he would fail without having
some experience with simpler preparations, I think one can learn just as much from failures as from successes.
Yet Aikimike, I would rather encourage you into understanding theory where you are weakest before even venturing into such involved experiments.
Meanwhile you can do some simpler organic preparations to get some practical skills.
Edit: Thread moved to Organic chemistry section.
[Edited on 18/8/2008 by Nicodem]
…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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Formatik
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Have a look at the OrgSyn procedure. For an idea on low yields with just conc. H2SO4, see this thread by Axt. Some physical and reaction data from Beilstein I 763: easily soluble in water, alcohol, more difficultly soluble in acetic
ether, even more difficultly soluble in ether, insoluble in CHCl3, ligroin, and benzene. Melts at 135 deg., forming CO2 and acetone; these two also
result by boiling with water, or warming with acids or alkalis. Its salts even decompose in the cold to eventually form acetone and carbonates. Gives
violet color with iron chloride, conc. KOH solution splits it into acetic and malonic acids. Letting it stand with H2SO4 forms citracumalic acid
C10H8O8.
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Sauron
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Trading off the hazard and expense of oleum for low yield is a good idea for a novice. There remains the CO hazard, best dealt with IMO by doing this
outdoors.
Once acid is obtained it has to be thoroughly freed from H2SO4 and preferably esterified for storage. The free acid will not keep unless rigorously,
scrupulously acid free by repeated recrystallizations from if I recall, EtOAc.
Also, go to the trouble of obtaining as many of the old preps referenced from Org.Syn. as possible. In several cases, the procedures were simpler than
in Org Syn and better yield. A careful comparison of about half a dozen procedures will arm you with the tools you need to get this right first time.
Also do yourself a BIG favor and buy anhydrous citric acid rather than the hydrated USP or BP acid.
[Edited on 19-8-2008 by Sauron]
Sic gorgeamus a los subjectatus nunc.
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ScienceSquirrel
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I would point out that Aikimike is quite young so encouraging him to make his own oleum and recrystallise from flammable solvents may not be the best
idea.
By my reckoning he will have taken his GCSE science exams this summer.
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Aikimike
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Science Squirrel- My age really should not be a factor here. yes I have just taken my GCSE exams- but what relevance is that? I have a real passion
for chemistry, all I want to do is learn. I have a safe well equipped lab in which I practice Organic Chemistry in preperation for A level and beyond.
I do have Oleum, a litre of it in fact. Its not dangerous unless it is mis-used. The same is true for solvents.
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ScienceSquirrel
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Like it or lump it society feels that as people get older they gain more responsibility for their actions.
Some people will not agree with me but I think that there is a difference between encouraging an eighteen year old to do an experiment and encouraging
a sixteen year old to do an experiment.
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Aikimike
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I do hear where you are coming from, but surely it should depend upon the actions and the intent of person, as well as there relative maturity. I know
of many 16 year olds who are markedly more intelligent than 18 year olds, as well as being more responsible and frankly more competent in a lab.
I disagree however that that belief is prominent throughout all of society, many of my teachers for example recognise my passion and treat me as an
equal, something which I do respect. In much the same was as I respect Sauron for his chemical experience, I respect him for his non-bias against me
because of my age.
Apologies for the OT- I shall try again with hot, conc H2SO4 and Anhydrous Citric Acid and report back.
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Klute
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I don't really want to disgress more than already done, but I hardly think Oleum is the kind of product that is only dangerous when misued. Not at all
like solvents.
Most solvents can be used without excessive safety precautions, basic common sense and there isn't much to be afraid off.
Oleum is another kind of beast. A single drop will eat through alot, even your skin. Not really the kind of liquid you transfer from flask to flask on
a bench. Even chemist with over 10-15 yeasr training take alot of precautions when handling such corrosive, they are dangerous even when correctly
used.
There is much to be planned before, and only lengthy experience can help you be prepared to what will happen when you handle such a reagent.
I mean, the bottle surely weighs over 2kg, how do you plan on transfering a small amount? Can you imagine what would happen if at that precise moment
you get a cramp? How are you going to take care of that little drop slwoly running down the beaker/flask while you have on hand full of heavy, fuming
liquid you shouldn't take your eyes off? Etc etc
I'm not implying your are not capable off facing such manipualtions strickly becasue of your age, but because for such reagents to be handled safely,
one needs in-depth training and especially experience, that I doubt you could have after passing a GCSE. Relative maturity is certainly not the sole
requirement for handling dangerous reagents.
There are much, much things to do with safer reagents, that can be very interesting and challenging. If you like chemistry as much, which is a very
good thing, think of your futur, and act safely. You would loose all of it if you burn your hand off, or turn blind.
This is just an advice. I remember how I was at your age, and in retroscpetive, I'm glad I couldn't acces Oleum and such, as I would surely have felt
confident enough to use it, and not humble enough to let it sit for a few years before even thinking of using it.
I know this is disgressing from the origianal topic, but I strongly feel that we can't just let it a 16 year old say he will use some oleum at home
without warning him of the consequences and disencouraging him to do it, for his own sake. You might thank us some day.
\"You can battle with a demon, you can embrace a demon; what the hell can you do with a fucking spiritual computer?\"
-Alice Parr
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Mush
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Method for preparing 1,3-acetone dicarboxylic acid diester and an intermediate thereof by using citric acid to catalyze oxidization of hydrogen
peroxide
CN103288629B
Abstract
The invention discloses a method for preparing 1,3-acetone dicarboxylic acid diester and an intermediate thereof by using citric acid to catalyze
oxidization of hydrogen peroxide. The method comprises the steps of: with at least one medium-strong acid as a catalyst and hydrogen peroxide as an
oxidizing agent, oxidizing citric acid in a water solution of citric acid at 0-100 DEG C to obtain 1,3-acetone dicarboxylic acid; and enabling the
obtained 1,3-acetone dicarboxylic acid to be subjected to an esterification reaction with low-level fatty alcohol to obtain the 1,3-acetone
dicarboxylic acid diester. The method disclosed by the invention is used for efficiently preparing the 1,3-acetone dicarboxylic acid diester and the
intermediate thereof, and is high in yield, small in pollution and short in reaction time; and the method is suitable for large-scale industrial
production and the economic efficiency is greatly improved.
Background technology
1,3-β-ketoglutaric acid diester and intermediate 1,3-β-ketoglutaric acid thereof are important organic synthesis and medicine intermediate, can be
used for the medicines such as synthesis inner mold nortropine, Ge Laqiongsi, benztropine, Strontium Ranelate.Therefore, the research carrying out
1,3-β-ketoglutaric acid diester and intermediate 1,3-β-ketoglutaric acid synthetic methodology thereof has important application prospect.
1,3-β-ketoglutaric acid diester obtains primarily of the esterification of 1,3-β-ketoglutaric acid (1,3-Acetonedicarboxylic acid) with alcohol, and
1,3-β-ketoglutaric acid is mainly by citrate oxidizing synthesis.The oxygenant being usually used in oxidizing citrate has oleum, and as the oleum
oxidation with 20%, environmental stress is large.The productive rate of the method product can reach 85%-90%, but from the viewpoint of operation
difficulty or ease, oxygenant or catalyst levels, production cost and production safety, the method device complicated operation, the large usage
quantity (weight ratio of citric acid and oleum is 7:30) of oleum, and oleum can send asphyxiant sulphur trioxide mist, meet water, organism and
oxygenant easily to set off an explosion, and there is aggressive.
In CN101475482 with 98% sulfuric acid for oxygenant prepares 1 at about 50 DEG C oxidizing citrate, 3-β-ketoglutaric acid, wherein, sulfuric acid and
citric acid mass ratio are 1:1-3, yield is about 69%, and the method has larger advantage compared with oleum, but its productive rate is lower, the
consumption of sulfuric acid is also comparatively large, the same insecurity that there is larger environmental pollution and produce.
Therefore no matter from the angle of economy, or from the viewpoint of protection of the environment and Sustainable development, all high in the
urgent need to development yield, to pollute 1,3-little β-ketoglutaric acid diester high-efficiency synthesis method.
Summary of the invention
In order to solve existing 1,3-β-ketoglutaric acid diester and intermediate 1 thereof, the low-yield of the preparation method of 3-β-ketoglutaric
acid and the problem of environmental pollution brought, the invention provides citric acid catalyzing hydrogen peroxide oxidation preparation 1, the
method of 3-β-ketoglutaric acid diester and intermediate thereof, while raising yield, obtain the raising of larger production efficiency with less
pollution.
The technical solution used in the present invention is:
The method of citric acid catalyzing hydrogen peroxide oxidation preparation 1,3-β-ketoglutaric acid, in lemon aqueous acid, with strong acid at
least one for catalyzer, take hydrogen peroxide as oxygenant, at temperature 0-100 DEG C, make citrate oxidizingly to obtain 1,3-β-ketoglutaric acid
Embodiment 1
Reflux condensing tube is being housed, agitator, citric acid monohydrate compound 210g (1mol) is added in the 50Oml round-bottomed flask of
thermometer, adding 50ml water makes citric acid dissolve, and drip 1ml98% sulfuric acid (0.018mol) wherein, raised temperature to 55 DEG C, now start
to drip 30% aqueous hydrogen peroxide solution 136g(1.2mol), observe bubble to emerge quickly and evenly, along with adding of aqueous hydrogen
peroxide solution, temperature of reaction raises gradually, after being added dropwise to complete, 85 DEG C of reactions 2 hours, evaporated under
reduced pressure water makes citric acid dissolve again, cooling, crystallization, suction filtration, wash with frozen water, dry product 1,
3-β-ketoglutaric acid 141g(0.97 mol), yield is 97%, purity is 97%, fusing point 135 DEG C (decomposition).
Embodiment 14
Reflux condensing tube is being housed, agitator, citric acid monohydrate compound 210g (1mol) is added in the 50Oml round-bottomed flask of
thermometer, adding 40ml water makes citric acid dissolve, drip 25ml 36% hydrochloric acid (0.29 mol) wherein, raised temperature to 65 DEG C, now
start to drip 30% superoxol 170g(1.5mol), observe bubble to emerge quickly and evenly, along with adding of superoxol, temperature of reaction raises
gradually, after being added dropwise to complete, 95 DEG C of reactions 1 hour, weigh after evaporated under reduced pressure water, obtain product
1, 3-β-ketoglutaric acid 142.2g (0.97 mol).1,3-β-ketoglutaric acid 142.2g (0.97 mol) is added respectively, ethanol 115g (2.5mol) and 50ml benzene
in the 500ml there-necked flask with water trap and reflux condensing tube, be heated with stirring to backflow, when the benzene of condensation on
water trap becomes clear, after esterification completes, through washing, extraction, the aftertreatments such as separatory, obtain product
1,3-β-ketoglutaric acid diethyl ester 196g (0.97mol), yield is 97%, and purity is greater than 96%.
[Edited on 23-11-2020 by Mush]
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Johnny Windchimes
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Unfortunately, I tried these Chinese patent methods (and a few other similar ones with tungstic and cobalt catalysts) and whilst I THOUGHT they
worked, they unfortunately did not
The 1,3 acetonedicarboxylic acid anhydride I assumed I made turned out to be not the 1,3 acetonedicarboxylic acid anhydride I assumed
I made once I ran a FTIR at school
https://www.sciencemadness.org/whisper/viewthread.php?tid=15...
Were you able to make them workable, Mush???
Quote: Originally posted by Mush  | Method for preparing 1,3-acetone dicarboxylic acid diester and an intermediate thereof by using citric acid to catalyze oxidization of hydrogen
peroxide
CN103288629B
Abstract
The invention discloses a method for preparing 1,3-acetone dicarboxylic acid diester and an intermediate thereof by using citric acid to catalyze
oxidization of hydrogen peroxide. The method comprises the steps of: with at least one medium-strong acid as a catalyst and hydrogen peroxide as an
oxidizing agent, oxidizing citric acid in a water solution of citric acid at 0-100 DEG C to obtain 1,3-acetone dicarboxylic acid; and enabling the
obtained 1,3-acetone dicarboxylic acid to be subjected to an esterification reaction with low-level fatty alcohol to obtain the 1,3-acetone
dicarboxylic acid diester. The method disclosed by the invention is used for efficiently preparing the 1,3-acetone dicarboxylic acid diester and the
intermediate thereof, and is high in yield, small in pollution and short in reaction time; and the method is suitable for large-scale industrial
production and the economic efficiency is greatly improved.
Background technology
1,3-β-ketoglutaric acid diester and intermediate 1,3-β-ketoglutaric acid thereof are important organic synthesis and medicine intermediate, can be
used for the medicines such as synthesis inner mold nortropine, Ge Laqiongsi, benztropine, Strontium Ranelate.Therefore, the research carrying out
1,3-β-ketoglutaric acid diester and intermediate 1,3-β-ketoglutaric acid synthetic methodology thereof has important application prospect.
1,3-β-ketoglutaric acid diester obtains primarily of the esterification of 1,3-β-ketoglutaric acid (1,3-Acetonedicarboxylic acid) with alcohol, and
1,3-β-ketoglutaric acid is mainly by citrate oxidizing synthesis.The oxygenant being usually used in oxidizing citrate has oleum, and as the oleum
oxidation with 20%, environmental stress is large.The productive rate of the method product can reach 85%-90%, but from the viewpoint of operation
difficulty or ease, oxygenant or catalyst levels, production cost and production safety, the method device complicated operation, the large usage
quantity (weight ratio of citric acid and oleum is 7:30) of oleum, and oleum can send asphyxiant sulphur trioxide mist, meet water, organism and
oxygenant easily to set off an explosion, and there is aggressive.
In CN101475482 with 98% sulfuric acid for oxygenant prepares 1 at about 50 DEG C oxidizing citrate, 3-β-ketoglutaric acid, wherein, sulfuric acid and
citric acid mass ratio are 1:1-3, yield is about 69%, and the method has larger advantage compared with oleum, but its productive rate is lower, the
consumption of sulfuric acid is also comparatively large, the same insecurity that there is larger environmental pollution and produce.
Therefore no matter from the angle of economy, or from the viewpoint of protection of the environment and Sustainable development, all high in the
urgent need to development yield, to pollute 1,3-little β-ketoglutaric acid diester high-efficiency synthesis method.
Summary of the invention
In order to solve existing 1,3-β-ketoglutaric acid diester and intermediate 1 thereof, the low-yield of the preparation method of 3-β-ketoglutaric
acid and the problem of environmental pollution brought, the invention provides citric acid catalyzing hydrogen peroxide oxidation preparation 1, the
method of 3-β-ketoglutaric acid diester and intermediate thereof, while raising yield, obtain the raising of larger production efficiency with less
pollution.
The technical solution used in the present invention is:
The method of citric acid catalyzing hydrogen peroxide oxidation preparation 1,3-β-ketoglutaric acid, in lemon aqueous acid, with strong acid at
least one for catalyzer, take hydrogen peroxide as oxygenant, at temperature 0-100 DEG C, make citrate oxidizingly to obtain 1,3-β-ketoglutaric acid
Embodiment 1
Reflux condensing tube is being housed, agitator, citric acid monohydrate compound 210g (1mol) is added in the 50Oml round-bottomed flask of
thermometer, adding 50ml water makes citric acid dissolve, and drip 1ml98% sulfuric acid (0.018mol) wherein, raised temperature to 55 DEG C, now start
to drip 30% aqueous hydrogen peroxide solution 136g(1.2mol), observe bubble to emerge quickly and evenly, along with adding of aqueous hydrogen
peroxide solution, temperature of reaction raises gradually, after being added dropwise to complete, 85 DEG C of reactions 2 hours, evaporated under
reduced pressure water makes citric acid dissolve again, cooling, crystallization, suction filtration, wash with frozen water, dry product 1,
3-β-ketoglutaric acid 141g(0.97 mol), yield is 97%, purity is 97%, fusing point 135 DEG C (decomposition).
Embodiment 14
Reflux condensing tube is being housed, agitator, citric acid monohydrate compound 210g (1mol) is added in the 50Oml round-bottomed flask of
thermometer, adding 40ml water makes citric acid dissolve, drip 25ml 36% hydrochloric acid (0.29 mol) wherein, raised temperature to 65 DEG C, now
start to drip 30% superoxol 170g(1.5mol), observe bubble to emerge quickly and evenly, along with adding of superoxol, temperature of reaction raises
gradually, after being added dropwise to complete, 95 DEG C of reactions 1 hour, weigh after evaporated under reduced pressure water, obtain product
1, 3-β-ketoglutaric acid 142.2g (0.97 mol).1,3-β-ketoglutaric acid 142.2g (0.97 mol) is added respectively, ethanol 115g (2.5mol) and 50ml benzene
in the 500ml there-necked flask with water trap and reflux condensing tube, be heated with stirring to backflow, when the benzene of condensation on
water trap becomes clear, after esterification completes, through washing, extraction, the aftertreatments such as separatory, obtain product
1,3-β-ketoglutaric acid diethyl ester 196g (0.97mol), yield is 97%, and purity is greater than 96%.
[Edited on 23-11-2020 by Mush] |
[Edited on 30-11-2020 by Johnny Windchimes]
~Incredibly profound and/or wise quote goes here~
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