Sciencemadness Discussion Board - Deuterated acetone.

Deuterated acetone.

Hermes_Trismegistus - 5-9-2004 at 08:49

Possible tabletop fusion

Could D-acetone be prepared in a small lab?

(I know that it would be probably be simpler to procure it from a supplier of NMR solvents)

Esplosivo - 5-9-2004 at 09:02

As I see it, it is impossible to replace the hydrogens in acetone with deuterium. It would also be near to impossible to create such acetone without complicated lab procedures, which at least in my case cannot be carried out due to lack of certain apparatus and chemicals.

Just to produce ethene with Hs replaced by D one would require D2O. I know D2O can be bought but if one wants to synthesize acetone from scratch well, I suppose it is better to buy it readily made.

[Edited on 5-9-2004 by Esplosivo]

Proteios - 5-9-2004 at 13:21

Yeah... I was recently at a Gordon Research Conference at which this was discussed..... Like cold fusion.. this is what happens when you get chemist.... writing about physics, about which they know squat!

In the cold fusion paper of salt lake city everyone knew instantly it was BS.... if they had had the neutron flux they had claimed...... they would all be dead from the ionising radiation rather than writing paper about discoving cold fusion.

There is a simple progression in energy states..... UV....soft x rays... hard x rays... gamma rays..... nuclear decay product (neutrons etc).....these boys.. like the previous ones claim to get the most activated products... with none of the daughter spinoff.... e.g. theyre full of it!

On the upside... such papers are always heavily cited.... as examples of poor science..... and they get to count a claim and a retraction as two publications.

Poor Science.

The sonoluminense is good stuff though.... some clever stuff there.

[Edited on 5-9-2004 by Proteios]

FrankRizzo - 5-9-2004 at 14:58

Proteios:

Did you happen to read this article?

http://www.spectrum.ieee.org/WEBONLY/resource/sep04/0904nfus...

Proteios - 5-9-2004 at 16:22

nope... but that what happens when you get people goin high profile and nailing their reputations to the mast. For those who DONT follow the literature on such things the history goes like this......
Salt Lake City boys go public (BEFORE SUBJECTING THEIR WORK TO PIER REVIEW) on the basis their discovery will revolutionise mankind. Of course it turns out to be complete tot and VERY simple to debunk for even a mediocre physist. But by now a lot of respectable people have egg on their faces.... this shameful article represents a bunch of people who pulled one of the biggest and most dumbass scientific blunders of all time..... and chose to do so before the worlds cameras... trying to bluff that they are not a bunch irresponsible amateurs. Basically they are trying to lie their asses outta the mess they made by rewriting history etc. Not a million miles from Bush invading Iraq cos those weapons of mass destruction were pointing at the US. The US is a funny place though.... that fact that he was wrong on such an important subject as War... or not.... doesnt seem to phase people.

JohnWW - 5-9-2004 at 17:55

The rate of cold fusion that Pons et al claimed to have discovered a few years ago, as the result of electrolysis with a Pd cathode (I think), was probably too slow for the intensity of the probable radiation given off (mostly fast deuterons and He-3 and He-4 nuclei, and gamma-rays, most likely) to be harmful, assuming it was for real.

Sigma-Aldrich probably sell hexadeuteroacetone, in view of the wide range of other deuterated organics they sell - but very costly. To make it, an excess of D2 gas would have to be catalytically reacted with carbon under extreme heat and pressure (similar to that in the SASOL coil-to-oil plant in South Africa) to form (mostly) CD4. Then the CD4 would have to be reacted with a halogen to obtain CD3Cl or CD3Br. Then this could be reacted with Mg to obtain a Grignard reagent, e.g. CD3MgBr, which would react with CO2 and an acid to give CD3COOH. Other CD3Br can be reacted with Li metal to give CD3Li, which reacts with CD3COOH and then water to give, finally, (CD3)2CO, which can be distilled from the aqueous solution. All this sounds very expensive.

John W.

[Edited on 6-9-2004 by JohnWW]

mick - 5-9-2004 at 21:30

Just thinking
calcium carbide + D2O would give you deuterated acetylene, then add some deuterated stuff across the triple bond would give you 2 deuterated carbons to start with.
Mick

BromicAcid - 5-9-2004 at 21:36

I remember reading somewhere that the exchange rate between hydrogen atoms on benzene in the presence of deuterated sulfuric acid favored the formation of deuterated benzene so much that it was a quite effective way of making high concentrations of deuterated benzene. Don't know if there are similar favoring equilibriums for deuterated acetone though.

Proteios - 5-9-2004 at 23:04

i remember reading this when CF first came out:

"The energy aspect of this field has another significant aspect. In one of their earliest papers, 3 Fleischmann and Pons made the following statement: —We have to report here that under the conditions of the last experiment, even using D2O alone, a substantial portion of the cathode fused (melting point 1554ºC), part of it vaporized, and the cell and contents and part of the fume cupboard housing the experiment were destroyed.“ Hence, a subsequent question to the reality of —cold fusion“ is its potential for weapons. The possibility of national security concerns, on top of the scientific and potential commercial ramifications, make —cold fusion“ even more interesting"

put simply... if you had that much thermalised energy from fusion products.... everyone in the lab would have died from the radiation flux.

JohnWW - 5-9-2004 at 23:55

That sounds MOST unlikely, because the H atoms in unsubstituted benzene, for all practical purposes, do not ionize, i.e. are completely non-labile.

Acetone is commercially synthesized starting from the combination of benzene and propene under pressure and heat, the first product being cumene (2-phenyl isopropane, or isopropylbenzene), which is oxxidized with oxygen to form a tertiary hydroperoxide, which then can be rearranged to form phenol (a product of equal importance) and acetone (which can be distilled off). So, if you could easily synthesize C6D6 and CD2=CD-CD3, you would have a good process for large-scale production of hexadeuteroacetone and either penta- or hexa-deuterophenol - IF there was a demand for large quantities of them.

For this purpose, C6D6 could be made by reacting CaC2 with D2O to form C2D2, which can be polymerized under heat and pressure to C6D6. The deutero-propene could be synthesized from some of the C2D2 made in the last reaction by some reaction resulting in a D and a CD3 being added across the triple bond; possibilities are condensation under great heat and pressure of C2D2 with CD4 (which would have to be made somehow, e.g. as above), or partial halogenation to C2DBr followed by reaction with Mg to form the Grignard reagent C2DMgBr which could then be reacted with CD3Br to form deuteropropene. The deutero-cumene could be made as above, and so on to get deutero-acetone and deutero-phenol.

John W.

BromicAcid - 6-9-2004 at 07:21

Please at least consider a thought before stating that it won't work, because this does work!

The deuterated sulfuric acid causes protonation of the benzene ring via the D3O+ cation, and upon protonation the C6H6D molecule can lose either of the hydrogens from the sp3 carbon to regain its aromaticity. If a large excess of deuterated sulfuric acid is used, total conversion to D6C6 is entirely possible and was at one time a method used to produce it.

[Edited on 9/6/2004 by BromicAcid]

Proteios - 6-9-2004 at 10:19

yup... if i were after D6 benzene.. thats how i would do it. Benzene is cheap.... D2O is cheap.... all you have to do is get some minor population of either the anion or cation.... and wait for a couple of days. A method thats quite common is H/D istopic substitions... look for protons that have either the highest or lowest acidity.... etc.

JohnWW - 6-9-2004 at 21:37

Quote:

Originally posted by BromicAcid(cut) The deuterated sulfuric acid causes protonation of the benzene ring via the D3O+ cation, and upon protonation the C6H6D molecule can lose either of the hydrogens from the sp3 carbon to regain its aromaticity. If a large excess of deuterated sulfuric acid is used, total conversion to D6C6 is entirely possible and was at one time a method used to produce it.

Do you have a reference to this? Because of the extra aromaticity stability associated with benzene, and its symmetry, such easy protonation by a simple non-oxidizing acid does not sound likely.

John W.

mick - 7-9-2004 at 01:04

Is it the Freidel Craft reaction, electrophilc substitution of aromatic hydrogen with deuterium
Mick

If you started with nitrobenzene or pyridine you should be able to do nucleophilic substitution of at least some of the hydrogens. Just thought 1,4-dinitrobenzene or pyrazine should do then all

[Edited on 7-9-2004 by mick]

svm - 7-9-2004 at 08:47

if you could get ahold of D2SO4, then I think that treating acetone with that would probably do the trick. C-D bonds are slightly stronger than C-H bonds, so you could eventually enolize/deuterate off all the hydrogens. you probably wouldn't get perfect incorporation of the D though.

you might also be able to do it with a base. something like sodium t-butoxide + deuterated t-butanol. however, if you're going to those lengths, may as well just buy it. Aldrich sells 10 mL of it for $22.

mick - 7-9-2004 at 09:35

I never thought I would see the day when I could mention all these names that I learnt a school.
I think you would end up with a condensation reaction, Claisen or Diekman or some one else.
mick

If you ever want to be realy famous get a reaction that works named after you

BromicAcid - 7-9-2004 at 09:50

Quote:

Do you have a reference to this? Because of the extra aromaticity stability associated with benzene, and its symmetry, such easy protonation by a simple non-oxidizing acid does not sound likely.

I've seen this in many sources but I will quote one of my hard copy books.

[Maitland Jones, Jr.; Organic Chemistry 2nd edition; pps 582-583, W.W. Norton & Co. 2000, 1997]

Quote:

The prototypal example of the substitution process is H/D exchange. If sufficiently acidic conditions are used, we can see the apparent non-reaction of HX with benzene is an illusion. When benzene is treated with D2SO4, the recovered benzene has incorporated deuterium, with the amount of incorporation depending on the strength of the acid used and the time of reaction. Ultimately, excess deuteriosulfuric acid will produce fully exchanged benzene Fig. 13.16).

From another section of the same area, a caption to one of the diagrams:

Quote:

If deuteriosulfuic acid is used, the initial addition must generate a deuterated cyclohexadienyl cation. Reversal of the reaction will generate benzene, but loss of a proton will give the exchanged benzene. In an excess D2SO4, all the proton of benzene can be exchanged for deuterons.

BTW, what do you mean by "extra aromaticity stability associated with benzene"? Why does benzene have extra aromatic stability, it is the matriarchal aromatic and it's stability is the stability to which aromatics are held, how can it have extra?

svm - 7-9-2004 at 11:34

mick, you're probably right. i hadn't figured on that. i know acetone can polymerize under acidic conditions.

a claisen condensation is typically with two esters, a dieckman cyclization is an intramolecular claisen condensation. so this isn't really either of those, but it's really close.

JohnWW - 7-9-2004 at 12:10

The symmetry of benzene, with all Hs and Cs equivalent, also provides a barrier to reaction with many reagents, especially non-oxidizing ones. Nitric acid, in forming a nitro-compound wiith a C-N bond, depends on its oxidizing a C-H bond.

John W.

mick - 7-9-2004 at 12:21

You end up with an alpha beta unsaturated ketone or some thing.
This from memory
mick

unionised - 7-9-2004 at 14:08

React calcium carbide and heavy water to give heavy acetylene. Catalytic reduction using D2 (from electrolysis of D2O) and Pd to give deutero ethene, add D2O across the double bond (under acid conditions, you might get away with phosphoric acid from P2O5 and D2O) to give deutero ethanol. Oxidise with KMnO4 (in soln in D2O) to give heavy acetic acid. Convert to the calcium salt and pyrolyses it to give d6 acetone.

I don't see this as being the most practical scheme , but it is possible.

BTW, acid catalysed condensation of acetone gives a whole bunch of products including mesitylene which could be used for synthesising benzene by reverse F-C alkylation.

I don't think that cold fusion works, so making heavy acetone would be a rather expensive game to play for no real prospect of success.

Marvin - 7-9-2004 at 14:50

mick, I thought youd said enough to solve this issue actually, it doesnt seem to have been picked up on.

Someone (Lets face it probably Organikum) posted an artical on an excellent total synthesis of benzene. Starting with the production of lithium carbide rather than calcium carbide probably because of contamination issues but the theory is the same.

Lithium carbide (more accuratly acetylide in this case) gets you deuterated acetylene. Easiest way from there is to use mercuric sulphate (I think its the sulphate) to hydrolyse to acetaldehyde. Oxidise gets you acetic acid. Heat CaO in the fires of hell to remove trace protium, CaO will not decompose until silly temperatures so I dont see this as a problem but any lab grade product sold will be contaminated. This gets you the calcium salt of acetic acid and ... ta da, pyrolyse to acetone. Everything up to the pyrolysis step should be high yeilding. There is probably a better way but while we are sticking to hypothetical situations this is from D2O as deuterium feed only and we dont contaminate any D2O with protium.

Attempting to use the cumene autooxidation process is absolutely(favourate word of chemistry professor coming up) diabolical. Thats the process used primarily to make phenol from benzene, the acetone is a byproduct. Industrially propene (used to make the cumene in the other process anyway) is hydrated to isopropanol and this is oxidised to acetone.

John seems to be still sticking to the belief that *alcohols* will not exchange deuterium when shaken with D2O dispite being told twice that this is common lab practice in NMR. Frankly I think you have about a hope in hell of convincing him of benzene exchange BromicAcid. Nitration and sulphonation mechanisms are standard degree fodder and they fully support benzene proton exchange and if they didnt both mechanisms are reversable anyway forcing overall proton exchange in strong mixed acid or sulphuric acid.

Ordinary acetone treated with sulphuric acid would condense, along with carbonisation I would expect and produce mesitylene amongst other things. Mesityl oxide mick is thinking of would be one very common product under less extreme circumstances along side phorone.

The C=O makes alpha hydrogens acidic and rather more reactive molecule generally (tautomerism) so some exchange would be expected in a mixture of acetone and D2O made slightly acidic or basic (higher risk of resin products with base). Youd need a very very large excess of D2O to get a high yeild of all D acetone. If you make acetone acidic with HCl you get an equilibrium between it and diacetone alcohol, so I think this method is at least possible.

The cold fusion experiment is very widely held to be a mistake in that neutrons were 'seen' due to BF3 counters being immersed in hot water and when this was done by researchers in a known zero neutron flux they also had a substantial reading.

There are a few research teams in the world still looking at cold fusion, where 'cold' is anything but plasma temperatures, and most of these believe that the reaction produces no neutrons (conveniently), and no gamma rays (conventiantly) or high energy particals (essentially any way of proving fusion beyond excess heat with the exception of the common lab contaminent helium most of them cant detect accuratly anyway) in stark contrast to any other hot or cold (meaning in this case muon catalysed) deuterium fusion ever observed.

In terms of replicating this particular scientific wet dream, which isnt really cold fusion at all, its a claim of hot fusion under easy conditions, you cant do it unless you have a neutron source to nucleate the solution during soundwave exposure. Doing this and then trying to detect neutrons from fusion in excess of the high neutron field you are putting in yourself is fraught with experimental problems. Neutrons are not easy things to work with.

Edit,

In the time taken me to post this unionised has latched on to the same basic method. Make acetic acid from acetylene and pyrolise the salt. I have a little more faith its workable, but then thats only because I cant currently think of a better one.

I dont think its a wasted excersize as thinking in these terms is a good way to grasp whats really going on in reactions, as well as working out reactions to a different goal than overall yeild. Also I expect the world market in fully deuterated acetone to be miniscule but its probably much more valuable than the D2O it can be made from.

[Edited on 7-9-2004 by Marvin]

Hermes_Trismegistus - 7-9-2004 at 16:51

Gentleman, I greatly appreciate the quality of your replies.

As for a tabletop neutron source, a Farnsworth Fusor should be adequate and is well within the sphere of the amateur scientist.

Thanks Kindly,
Hermes Tris.

Proteios - 8-9-2004 at 00:32

chuckle... the Farmsworth Fusor is for amateurs.... thats why... when I need a reliable Gigawatt power source, but dont want to glow in the dark afterwards... I reach for Mr Fusion @.

JohnWW - 8-9-2004 at 02:29

Quote:

Originally posted by Marvin
(cut) John seems to be still sticking to the belief that *alcohols* will not exchange deuterium when shaken with D2O dispite being told twice that this is common lab practice in NMR. Frankly I think you have about a hope in hell of convincing him of benzene exchange BromicAcid. Nitration and sulphonation mechanisms are standard degree fodder and they fully support benzene proton exchange and if they didnt both mechanisms are reversable anyway forcing overall proton exchange in strong mixed acid or sulphuric acid. (cut)

You have quoted me incorrectly! I said that the non-labile Hs in C6H6, which for all practical purposes do NOT ionize, should not exchange with those of pure deuterated D2SO4, also because of the symmetry of benzene, except very minutely. This is UNLESS other reagents and conditions are present which will result in sulfonation, with formation of a C-S bond i.e. deuterated phenylsulfonic acid, C6H5-SO2-OD. BUT, for the deuterated benzene (with Ds from the D2SO4) to be fully recovered afterwards from this compound, any such sulfonation would have to be fully reversible. (Reversibility looks unlikely, though, except under extreme conditions). Besides, sulfonation by H2SO4 occurs much less readily than nitration by HNO3(catalysed with H2SO4), because in the former case the reaction proceeds at an appreciable rate only with FUMING or pyro-sulfuric acid, H2S2O7, or with SO3, but not with H2SO4, while in the latter case there is the oxidizing nature of HNO3.

As for alcohols not exchanging Hs with D2SO4, I only went so far as to say that the rates of such an exchange would be much less than that of carboxylic acids due to the much lesser degree of ionization; and that it would practically not happen for other than the shortest-chain alcohols, because higher alcohols (which are waxes and oils) are practically insoluble in water.

In future, please take care to not quote me incorrectly. I hate it!

John W.

mick - 8-9-2004 at 10:50

This is from personal experience.
In NMR experiments a D2O shake involves adding a drop of D2O to a solution of the compound which is usually dissolved in deuterated chloroform or DMSO, shaking and re-recording the NMR. The proton signals due to alcohols, amines, amides, aldehydes and carboxylic acids will disappear due to exchange and a signal due to HDO will appear.

You are right about the hydrogens in benzene not being ionised but I think the deuterium exchange is through an addition/elimination mechanism, it occurs with hydrogen but that just gives non-distinguishable benzene ie no detectable reaction. The final products of sulphonation and nitration form slower but are non-reversible and so are the ultimate products that are isolated and identified.

mick

Marvin - 9-9-2004 at 05:03

"You have quoted me incorrectly!"

No John, I didnt quote you at all.

"...This is UNLESS other reagents and conditions are present which will result in sulfonation"

"any such sulfonation would have to be fully reversible. (Reversibility looks unlikely, though, except under extreme conditions)"

Sulphonation is fully reversable. I suggest you read up on sulphonation of toluene, and of napthalene (compounds with more than one isomer), and the effects of long versus short time periods and high versus low temperatures. These are effects that only have meaning for a reversable system. Nitration is also reversable, but oxidation side reactions tend to eat away at yeilds.

Sulphonation does not have to be invoked as the primary cause, if you look at sulphonation or nitration which is commonly illustrated in degree textbooks.

C6H6 + NO2+ => [C6H6NO2]+

It forms a meisenheimer complex, and this can either spit out H+ to form nitrobenzene, or NO2+ again to get back to where we started. The important thing though is there is nothing special about NO2+. Its just the electrophile that results in production of nitrobenzene, its not the only one though and to be fair its present in really tiny amounts. H+ is present in massive amounts so we'd expect the same thing to happen,

C6H6 + H+ => [C6H7]+ => C6H6 + H+

Thats the proton exchange mechanism I'd have my money on and judging by micks reponse I think he'd agree, but I dont see why the reversable sulphonation of benzene would not provide a slower but also valid mechanism at higher temperatures.

Coming up with undergrad theoretical excuses for why something doesnt work after people have allready stated that it does - and then not bothering to check in a book or online - is the action of an idiot.

JohnWW - 9-9-2004 at 11:49

Stop engaging in character assassination, Marvin! Just because someone says off-the-cuff that something works does not necessarily make it work. The problem is that so many people who allege that some or another reaction works fail to fully specify the conditions of the reaction e.g. temperature/pressure/acidity/solvent, omit to mention additional reagents which may be needed e.g. catalysts or acidifying agents, or mis-identify reagents e.g. as H2SO4 instead of H2S2O7 which is standard for aromatic sulfonation. That is why what is stated to happen so often fails to agree with theory, as in this sulfonation/nitration case. Please desist from penalizing me for these other peoples' failings.

Besides, aromatic sulfonation seems to be reversible only under conditions which are not the standard ones for sulfonation, particularly the presence of water. As for aromatic nitration particularly of benzene, its mechanism is significantly different from sulfonation; and NOT ONE of several reference books I have consulted, or a Google search, indicates that nitration may be reversible, to form the original reagents (particularly HNO3) from the nitro-compounds and byproducts, under ordinary conditions in the same reaction mixture!

I observe that you did not further address the matter of the circumstances under which alcohols' deuteration can occur, which I also raised, in your latest post. (Selective use of information, again.).

John W.

Proteios - 9-9-2004 at 18:18

chuckle.... im with marvin on this one... dont be so sensitive and show some humilty jonny!

and for those who might even consider the reaction....... so what if you get some sulfonation..... benzene is an absolute doddle to separate by distillation

Oh yeah... and jonny.. when u be in a hole... stop diggin

EDIT:
"Please desist from penalizing me for these other peoples' failings. ".

... man thats a real nice attitude u got there jonny!

[Edited on 10-9-2004 by Proteios]

JohnWW - 10-9-2004 at 00:44

You added NOTHING new to the matters under consideration, Proteios. Keep out of polemics which do not concern you.

John W.

----------------------------------------------------

Please refrain from these kinds of comments. Everybody is free to post in this thread as long as he or she obeys the rules. Furthermore, enforcing the rules is a matter of STAFF.

[Edited on 10-9-2004 by vulture]

Proteios - 10-9-2004 at 10:04

Quote:

Originally posted by JohnWW
You added NOTHING new to the matters under consideration, Proteios. Keep out of polemics which do not concern you.

John W.

----------------------------------------------------

Please refrain from these kinds of comments. Everybody is free to post in this thread as long as he or she obeys the rules. Furthermore, enforcing the rules is a matter of STAFF.

[Edited on 10-9-2004 by vulture]

LMAO.... that brightened up anotherwise dull morning!..... barking orders about polemics indeed!... funny stuff!

However The Admin seem keen to desist this kinda behaviour.... so i guess im gonna have to leave my honour undefended this time.....but rest assured I take such critisism very seriously.........

....chuckle....

[Edited on 10-9-2004 by Proteios]

----------------------------------------------
Same goes for you, if you have nothing to contribute to the thread, don't stir up shit.

[Edited on 11-9-2004 by vulture]

BromicAcid - 10-9-2004 at 16:19

Entery from the Chemical Abstracts, around 1955

If further questions result information from the actual article is linked below.

Also, additional information could be aquired by looking up the article on the origional preparation of C6D6 from benzene and D2SO4 at:

C.K. Ingold, C. G. Raisin, C. L. WIlson, C. R. Bailey and B. Topley, J. Chem. Soc., (1936); see also L. H. P. Weldon and C. L. Wilson. ibid., 235 (1946)

c6d6a.jpg - 82kB

JohnWW - 11-9-2004 at 00:15

Because that is a Journal report of one researcher's apparent finding in 1954 or 1955, it is not necessarily authoritative. The test would be if other researchers, on reading the report, found they could essentially duplicate it, and add other and more precise details as to the reagents used, their purity, the purity of the alleged product, and the reaction conditions, and indicate or suggest improvements to the method. Only then would it appear in textbooks or manuals.

Even if that equilibration reaction worked as stated, an enormous excess of deuterated reagent would have to have been used to obtain such pure C6D6 from C6H6 - possibly such that the synthetic method I described previously, involving reacting CaC2 with D20 and polymerizing the C2D2 produced to C6D6 under heat and pressure, may be more economic. The author does NOT say how much D2SO4 he used per unit of C6H6 - a glaring omission!!.

That 1955 researcher does not specify relatively how much SO3 he "distilled" into his D2O, including also the density of the reagent he used, although he says later he used "51-2% D2SO4" without saying how he measured this concentration. Bearing in mind that it is an heterogenous reaction between two immiscible phases, sulfonation, although reversible under certain conditions requiring water/heavy water to be present, proceeds unacceptably slowly with H2SO4, and would be even slower with D2SO4 because of the greater mass of D; and MUCH slower again with diluted 51% D2SO4. He, in fact, says he had to shake the mixture (consisting of two phases, the C6H6 and the aqueous diluted D2SO4) vigorously for 10 days under dry N2!! For a large-scale production process, that would probably be regarded as an unacceptable holdup time for a single reaction step, in my opinion as a chemical engineer. Moreover, he does NOT state the % yield of equilibration reaction, which would be reduced from 100% if the reaction was not fully reversible - another absolutely glaring omission!

Either that, or it was not D2SO4 he used, but instead D2S2O7, deuterated "fuming" sulfuric acid (and the reaction was then reversed or partly reversed by adding D2O), which reagent, I repeat, is standard for sulfonation in chemical industry.

John W.

mick - 11-9-2004 at 01:39

If you ran it as a continuous process industrially a residence time of 10 days should not be a problem
mick

Proteios - 11-9-2004 at 07:11

There is nothing wrong with this experimental (if you read the whole thing.. there is enough info to reproduce the experiment). Clutching at straws like.....not everything in the literature is correct, or ....but some other side reactions are theoretically possible, is the last refuge of a academic scoundrel.

I could reproduce this work fine.

1) Distill your SO3 into into an ampoule with a teflon ring style seal. Distil some of this into your D2O.... probably a real fiddly reaction.... but straightforward. Mass balance gives you your %. Normally you wouldnt bother saying things like this in an experimental....its too trivial.
2) Its stated the reaction is an equilibirum. At the beginning all the H is on the benzene.... all the H/D is equally in all positions. If it were me.....I would just use a ratio of 1000D:1H for a single pot synthesis. That should give you 99.9% D benzene.

If you were an isotope lab you would probably do this in 2-3 steps with 2-3 different H/D water.... all of which are easily recylable.
As for the sulfonation.... give it up! As i said earlier.... benzene is v. easy to separate by distilation anyway and sulphonation usually requires much more extreme circumstances.

If you check the jpg you will find that this technique is 'similar'.... to that used by...... i.e. it has already been reproduced: this is a GOOD AND STANDARD LITERATURE SYNTHESIS ...... ACCEPT IT!

mick - 11-9-2004 at 13:00

I have tried to do a citation index search for the ref above to see how many people have mentioned it, but I cannot get through from home, I will check it out at work.
I think the people who did this stuff in 1954 did a good job with the stuff they had. I class myself as an organic chemist now, but I do not think I would have any problem following what they said and expect 90%+ yield on the first run. I could even check it out on the old NMR (the one where I work is obselete but it still works) and tell you if the if the second deuterium goes para to the first. I could even do a rate of exchange graph. The only problem I have found with old information is the analysis is not as good as today. The practical stuff is better than today. Sintered glass filters are good for increasing your yield on a small scale, glass does not show up on most analytical techniques but when it implodes under vacuum where has all the glass gone, I think it increases yields on a research papers.
Sorry about this but you should not critisise the work of a good chemist just because he did it in 1954.
Peer review is good and I am sure the people who published the paper in the 50's were checked out.
Unpeer review does not sound quite right to me.
mick

JohnWW - 11-9-2004 at 13:35

Quote:

(cut) I would just use a ratio of 1000D:1H for a single pot synthesis. That should give you 99.9% D benzene.
(cut)

1,000 Ds to replace 1 H on benzene? An UNACCEPTABLE waste, having regard to the cost of D2O used to make the D2SO4, as well as the 10 days holdup required!! Together, these two factors would require enormous reaction vessels to be used, for very small amounts of C6D6 produced. The alternative I suggested, via CaC2 and C2D2 and polymerization, is certainly more economic than that.

Having run out of better ideas, you now stoop to calling me an "academic scoundrel"! Who is REALLY the "academic scoundrel"? Certainly, anyone who is so wasteful with expensive reagents like D2O just has to be the real "academic scoundrel".

It looks like just "sour grapes" on your part.

John W.

mick - 11-9-2004 at 14:40

But? if you ran it as a continuous process with the right pumping speeds and the right take off rate, you should be able to re-circulate most of the stuff

mick

typo
typo 2
Typo 3

[Edited on 11-9-2004 by mick]

[Edited on 11-9-2004 by mick]

[Edited on 11-9-2004 by mick]

mick - 11-9-2004 at 15:34

It is a bit like fractional distillation.
mick

Proteios - 11-9-2004 at 16:06

man... for a guy who claims to be a chemical engineer.... you certainly do make some dumbass statements.... I take it you now accept the reaction is
1) CORRECT... and youve given up that.... 'but i can think of a possible side reaction... therefore.... nomatter what teh literature says... it cant work'
2) IT IS SIMPLE... doesnt require handling gases... high temperature... with all the cracking problem that will ensue

Seeing as you clearly arnt able enough to figure it out for youself....... The 1000 fold excess of D2O will be 99.9 % pure by the time you finish...... well you could either use it again..... sell it on.... or send it back to the D2O plant for repurification. The idea that you would throw it aways is so stupid Im shocked that anyone would be so limited to suggest it.

I deal with lots of isotope synthesis..... Yield isnt really something that bothers me. The factors considered in a synthesis are
1) SIMPLICITY.... a point on which the one pot aqueous synthesis wins hands down on.
2) Ease of purification..... in this case V. Simple
3) recovery of isotope..... again.... in this case, V. simple

JohnWW - 11-9-2004 at 19:35

Just very slow, using or least requiring the purchase and acccommodation of a grossly excessive amount of an expensive reagent (D2O) even if it may be possible to reuse some of it, requiring an ENORMOUS reaction vessel for the amount of desired product produced (because of the enormous excess of D2O needed and the 10-day holdup), and hence inefficient and excessively costly, that's all. Even if the reaction works, these factors would certainly call it into question as to its commercial practicality, and must make it uncompetitive with alternative methods involving direct use of D2O, e.g. via carbide, on a large industrial scale.

Unless, of course, suppliers, or a monopoly supplier like Sigma-Aldrich, of deuterated chemicals simply do not care how much they cost to produce even if there are cheaper methods, and can rip consumers off as the result because of inadequate competition - at least until patents for the cheaper methods which they are "sitting on" expire. You say, "I deal with lots of isotope synthesis" - perhaps you work for such a company which is deliberately suppressing cheaper process methods in this way?

By your own admission, "Yield isn't really something that bothers me" means that you have NO concept or appreciation of process economics, Proteios, as well as no regard for the efficiency of reactions involving expensive reagents. Go back and do a course in it, at your local chemical engineering department (where do you live?), and then come back here. Ordinary (non-monopoly) chemical manufacturers would go broke if their staff had your sort of attitude.

John W.

[Edited on 12-9-2004 by JohnWW]

Proteios - 11-9-2004 at 20:13

Yeah... thats right... yield doesnt bother me..... Im interested in gettin the right isotope in the right form.
Again, the important factors are:
SIMPLICITY
RECOVERY OF ISOTOPE

D2O is cheap.... as i have said previously if you were doing batch runs you would do the reaction 3 times..... each with a H/D ratio of 10:1.
Take about a month.....and yeah... i know what your gonna say... thats commecially unacceptable.... but thats just wrong....the labor involved, which will be the largest cost in all of this, is nominal.... it only takes a few hours at most....

The alternative requires
1) Custom made kit
2) Lots of labor
3) Difficult conditions. Its funny that you were prepared to rubbish the literture synthesis upon little other than prejudice... and now you say that another reaction... for which you have no conditions, or procedure will be superior. However the reaction involves temperatures capable of breaking bonds.... this is gonna be a messy reaction. The conditions are gonna be awkward.... high temperture gases, and probably high pressure too. The separation of products may also not be trivial.

By comparison the LITERATURE single pot synthesis is better. You also sound like unless a synthesis is possible on a kilotonnes scale... its not worth doing. Isotope synthesis does not work like this.

Marvin - 12-9-2004 at 03:17

"Stop engaging in character assassination, Marvin! "

You post opinions in areas you clearly have weak understanding, you argue that you are right providing no new information and you fail to check anything in books or on the internet. If you consider these part of your character then yes, I am engaged in character assination and will do so as long as you give me cause to.

"The problem is that so many people who allege that some or another reaction works fail to fully specify the conditions of the reaction "

I'm sorry you think the brand of labcoat, the god you have to prey to beforehand and the exact size and shape of the ceiling tiles were not mentioned. We'll try harder. The reaction itself was described correctly, so the excuse that you disagreed because other people make mistakes doesnt hold water, deuterated or otherwise.

"That is why what is stated to happen so often fails to agree with theory."

No, you were spouting theory based on an assumed mechanism, they were describing what actually happens by experiment. The fact that your grasp of theory is insufficiant to describe the real world is something we all have to deal with, if it were possible to predict everything perfectly we wouldnt need the lit. However when presented with working and reliable information that disagrees with your understanding you automatically assume they must be wrong, and you post a rapid reply based on your own gut reaction that you then defend regardless of how much evidence mounts against it. This goes among a vast number of other rapid thoughtless posts you shotgun over the whole forum without aparently bothing to check ANYTHING. I cant remeber you posting one useful reference, one quote from a book, one relavent URL to back up your arguments.

"Please desist from penalizing me for these other peoples' failings"

Perhaps a summery of the d6 posts will bring this issue into focus.

BromicAcid claims sulphuric acid and benzene can be used to make d6 benzene.
You assume a mechanism, and disagree based on it.
BromicAcid posts a mechanism and explains it and Proteios agrees.
You object with a reason and ask for a reference.
mick points out an example of why your objection isnt valid.
BromicAcid gives a reference and a quote that supports the mechanism and the practical observation and asks why you think your objection is still valid.
You answer with an incorrect assumption about nitration, and electrphilic substitution generally.
I mention nitration and sulphonation standard mechanisms support the mechanism and that these are in any standard degree textbook, trying to indicate gently you should look them up.
You restate your case exactly as before aparently without checking or adding anything new.
mick posts in support of the exchange mechanism,
I post an explanation of BromicAcids mechanism in the context of nitration.
You blame inaccurate or incorrect descriptions by other people for the reaction failing to agree with 'theory'.
BromicAcid posts an entry from chemical abstracts, and a scan of a reference with enough information to actually do the experiment and predict the success of the result beforehand.
You argue that a single reference isnt conclusive and that other researchers would have to have succeded for it to be valid. Dispite this reference being in support of 2 other previos reports having claimed the same thing. You also argue that the conditions are not accuratly enough described (They are if you want to replicate it) and that amounts of reagents used were not mentioned (Irrelavent because this is an isotopic exchange and they give a value for success based on ratio of reactants so you can predict this).

Now. How is it other peoples failings that are the cause exactly?

"Besides, aromatic sulfonation seems to be reversible only under conditions which are not the standard ones for sulfonation, particularly the presence of water. "

Hmm, presence of water, other than its formation from the reaction going forward for example? Its not the case with Oleum, but this is not common in labs, most compounds will go with sulphuric acid alone including benzene if heated. You are letting what goes on industrially cloud the actual chemistry. Indistrial conditions are one specific case of how a reaction can be done, not the be and end all of the reaction.

"I observe that you did not further address the matter of the circumstances under which alcohols' deuteration can occur, which I also raised, in your latest post"

At the time you wrote this, and for several hours before your post, my post in the other thread relavent to alcohol exchange covered this, but since you require some extra information....

The reaction occurs rapidly monday to saturday in any month with an 'r' in it. For protons the reaction fails 18 additional days in the year sheduled in advance during the remaning months. Deuterium being a minority isotope only gets 2 weeks off a year due to its smaller union. The unions dont merge because protons object to deuterons eating all the free food during meetings and singing 'we ate all the pies' as a misdirected backlash at mass predudice. Chemists are advised to take their holiday during this time and to sign up for a newsletter indicating when either union plans to go on strike.

"Selective use of information, again"

As opposed to discussing things in the complete exclusion of information, I assume.

"possibly such that the synthetic method I described previously, involving reacting CaC2 with D20 and polymerizing the C2D2 produced to C6D6 under heat and pressure"

Hmm, you mean the method Organikum posted a scan of a detailed refernce for over a year ago that gives specific conditions and uses lithium carbide to avoid contamination with residual Ca(OH)2?

For conditions to make d6 benzene from D2O the acetylene way check out Organikums 30-3-2003 post in the first page of the benzene thread.

"For a large-scale production process, that would probably be regarded as an unacceptable holdup time for a single reaction step, in my opinion as a chemical engineer. "

Oddly enough my textbooks fail to mention d6 benzene as a high tonnage chemical, I'll just scrawl it in above sulphuric acid and leave the amount per year blank.

mick, thats a good point, if it were to be done industrially you wouldnt use a batch process, youd use a counter current continous process and get 99%+ d6 bezene out one end and probably <5% D2SO4 out the other. Another possability is that someone would work out conditions for making a stable emulsion and that would really decrease the time needed.

Proteios, I agree, 1000:1 would impact on the deuterium content of the D2O only very slightly, but getting th D2O back would be problematic. Cost is usually not much of an issue as only tiny amounts are usually needed (eg tracer studies) and ease of production and speed are important. Side reactions might cause some loss, sulphonations etc with such a large excess of D2SO4, might make seperation difficult afterwards.

Again, its thinking about a problem with different objectives than usual. Lab chemists need to be flexible, its good to have this kind of input.

mick - 12-9-2004 at 05:59

The paper BromicAcid found has been cited at least 48 times and many of these are from pre-net days, when you had to spend time and money to get a reference, if it was a waste of space I do not think anyone would have bothered. I read in another thread about scams. The current one seems to to publish a crap paper in a crap journal and you and your friends publish as many papers as possible all citing the same paper and when you apply for a research grant you get priority because you have been cited.
I was luck, I got my name in print in 1992 so people refer to the stuff because it is on the net (22 hits so far, nice to know that some one has read your work and thought it was worth mentioning). If it had been a few years earlier, no abstract or full text on the net I am sure no one would have bothered. Any way back to subject, for most applications 99%+ isotopic concentration would be OK, it is only when you are talking 99.9%+ etc you end up a different situation. Then as few hydrogens get near to your process as possible, and cost would not be a consideration.
mick

JohnWW - 12-9-2004 at 10:08

That is why a lot of incorrect, or grossly inefficient, chemistry gets into print - because being cited, i.e. getting one's name in print, gets you research grants, scholarships, or jobs. I wonder how much of the reported uncorroborated results were simply "cooked".

That was probably why, back in 1954 or 1955, a highly inefficient method of producing hexadeuterobenzene, was submitted to the J.A.C.S.. I simply cannot believe that a much more efficient, and certainly more rapid, method of producing it has not been discovered and developed for large-scale production in the 40 years since then. If it is still used for the purpose, the commercial producers must be simply "sitting on" the patents for the better methods - and are certainly not letting out any trade secrets.

John W.

[Edited on 12-9-2004 by JohnWW]

JohnWW - 12-9-2004 at 10:30

Marvin: Is regurgitating what has already gone all you can do, along with name-calling? Are you that lacking in originality and credible scientifically-based responses? People, especially on this forum, are not fooled by such sheer quantity of repeated verbiage, especially as it has been selectively picked and "slanted".

I stand by what I have written, and would only alter it to consolidate it. You do not seem to know the difference between merely doing chemistry, and doing good chemistry and especially efficient and economically viable chemistry (with regard also to my previous post on this thread), unless it is just a case of "sour grapes" for not previously appreciating this.

John W.

mick - 12-9-2004 at 10:44

Pass
mick

Proteios - 12-9-2004 at 11:42

this is starting to look very undignified jonny......

Having been shown to be catagorically wrong on the point:
QUOTE JONNY
"That sounds MOST unlikely, because the H atoms in unsubstituted benzene, for all practical purposes, do not ionize, i.e. are completely non-labile."

"Because of the extra aromaticity stability associated with benzene, and its symmetry, such easy protonation by a simple non-oxidizing acid does not sound likely. "

You now say... well its very inefficient..... a point which is again wrong in every important aspect, and that you BELIVE there is a better reaction to produce tonnes of the stuff in a wink of an eye for the cost of an extra value meal..... but of course offer nothing to back this up. This argument has the logical appeal of "Antractica doesnt exist because I have never seen it". The bottom line is Jonny that you were ABSOLUTELY WRONG in you initial arguments that this synthesis was impossible. ACCEPT IT.

If I had to do and experiment with D6 benzene.... i would buy the stuff.....its cheap and easily available. If i had to make the stuff..... I would use the above literature proc. Its SIMPLE, labour effiecient, and it works. The idea that I would waste months figuring out reaction conditions/purification protocols and several tens of thousands of dollars building kit for some fiddly hot gas reaction somehow doesnt have the same appeal.

AGAIN THIS IS LAB SCALE WORK.... NOT HEAVY INDUSTRY!

Proteios - 12-9-2004 at 11:55

Quote:

Originally posted by JohnWW
Marvin: Is regurgitating what has already gone all you can do, along with name-calling? Are you that lacking in originality and credible scientifically-based responses? People, especially on this forum, are not fooled by such sheer quantity of repeated verbiage, especially as it has been selectively picked and "slanted".

I stand by what I have written, and would only alter it to consolidate it. You do not seem to know the difference between merely doing chemistry, and doing good chemistry and especially efficient and economically viable chemistry (with regard also to my previous post on this thread), unless it is just a case of "sour grapes" for not previously appreciating this.

John W.

always banging the chemical engineer drum about sulfonations..... and always complaining about character assassinations:

"Stop engaging in character assassination, Marvin!"
posted on 9-9-2004 at 07:49 PM

"There is nothing more for me to say on this matter; I know what the facts are. Please stop engaging in hubris and character assassination, and selective use of information, Chemoleo, for having been beaten to the point. Are you jealous? "
posted on 8-9-2004 at 02:41 AM

Im sure ive said this before: but for someone who gets things wrong as frequently as you jonny, youve got a real nice attitude.

Heres a line for the narrow minded.....You dont seem to understand the difference between Heavy industry, excomony driven chemistry, and isotope synthesis.

JohnWW - 12-9-2004 at 12:55

Are you not aware, then, that Sigma-Aldrich (in particular) make and sell commercially isotope-substituted chemicals, especially deuterated chemicals? Production of deuterated and other isotope-substituted compounds thus has EVERYTHING to do with process efficiency and economics.

Even for small laboratory-scale preparations of deuterated compounds in university laboratories, especially if a constant supply of them is needed and the desired ones are not commercially available, I am very sure that the university's Regents would want the maximum economies in the use of expensive reagents. No university has unlimited funding, in this day and age - even if things were different in the mid-1950s.

John W.

Proteios - 12-9-2004 at 14:04

Jonny... as you couldnt be bothered to read it the first time... here it is again!

Quote:

Originally posted by Proteios
If I had to do and experiment with D6 benzene.... i would buy the stuff.....its cheap and easily available. If i had to make the stuff..... I would use the above literature proc. Its SIMPLE, labour effiecient, and it works. The idea that I would waste months figuring out reaction conditions/purification protocols and several tens of thousands of dollars building kit for some fiddly hot gas reaction somehow doesnt have the same appeal.

AGAIN THIS IS LAB SCALE WORK.... NOT HEAVY INDUSTRY!

READ THE THREAD JONNY

mick - 12-9-2004 at 14:21

Sigma-Adrich do not manufacture basic deuterated solvents, they might buy them in and might use them to manufacture high value deuterated chemicals, there are only so many primary sources of these type of chemicals.
We had a thing in the papers here (UK) about some one using osmium tetraoxide in a dirty bomb. If you want to buy osmium tetraoxide I think it all comes from the same place whether you buy it from Aldrich, Fisher etc. If anyone started to buy enough stuff to make a dirty bomb I think the manufacturers
would know. .
PS D2O is not very expensive if you buy it in bulk. Deuterated chloroform is only 6 UK pounds for a 100g and deuterated DMSO (with a lot of deuterium) is 60 UK pounds.
mick
typo

[Edited on 12-9-2004 by mick]

A warning for all of you

vulture - 12-9-2004 at 14:24

1) This is degenerating into a flamewar
2) Don't double post, edit your posts!
3) Keep it on topic. The thread says deuterated acetone, NOT benzene.

I won't tolerate any more shit. If someone, I don't care who, is going to continue this vendetta, this thread is closed. No exceptions.

JohnWW - 12-9-2004 at 14:32

Quote:

Originally posted by mick
Sigma-Adrich do not manufacture basic deuterated solvents, they might buy them in and might use them to manufacture high value deuterated chemicals, there are only so many primary sources of these type of chemicals.

Wrong - unless they have changed their stock radically in the most recent years. I happen to possess one of their catalogs, of several years ago, in which they list deuterated chemicals for sale.

John W.

mick - 13-9-2004 at 09:01

Owe you an apology JonnyWW, Aldrich-Sigma do manufacture deuterated solvents though their subsidary Isotech.
Apparently benzothiophene, benzenethiol and p-methylbenzenethiol can be per-deuterated with D2O containing dissolved metal salts at 250-315 oC and then desulfurizing the products gave per-deutero ethylbenzene, benzene and toluene in >95% yield. That all the abstract says.
mick

[Edited on 13-9-2004 by mick]

I meant to put this in the D2O thread, sorry
mick

[Edited on 13-9-2004 by mick]

JohnWW - 13-9-2004 at 10:06

Thank you, Mick.

John W.

Beware

vulture - 13-9-2004 at 10:55

Seems like my warning wasn't enough. You're walking a very thin line here.

Besides, refrain from posting single line posts.

minor excursion

halogen - 14-11-2004 at 05:13

Is DF worse than HF
And Thallium deuteride makes an hbomb green if so, pray it happens and help some foreign country with nuclear technology. Say the Tl is a nuclear catalyst or something.

unionised - 14-11-2004 at 06:47

Thanks for letting us know about your minor excursion. Please tell us when you are back on the planet Earth.
Or, to put it another way, WTF are you on about?