That electrolytic oxidation

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Author	Topic: That electrolytic oxidation
sparks Hive Bee	posted 01-21-2000 02:54 AM I was reading the patent text on rhodiums site. They claim very high yields (up in the 90's) from a very simple process. The nice thing is that the electrodes are graphite (anode) and stainless steel (cathode). No need for palladium or platinum. The produced epoxide is rearranged to the ketone with LiI which may be a bit tricky to get, but an alternative is to go via the diol to get the ketone. A dipolar aprotic solvent (acetonitrile,dimethylformamide,etc) is needed. Are there any other more readily available solvents that can be used? Does anyone have any firsthand info on this process? Any and all input are appreciated.
sparks Hive Bee	posted 01-21-2000 03:50 AM Is ethyl acetate completely out of the question? If so, why?
Osmium PimpBee	posted 01-21-2000 05:31 AM Ethyl acetate isn't a dipolar aprotic solvent like acetonitrile or DMF, it's pretty non-polar. It won't mix at all with the NaBr and water. I don't know if it works or not, but I guess the inventors had good reasons to use the other (much more expensive!) solvents. You might want to check this thread too: http://hive.lycaeum.org/ubb_board/Forum5/HTML/000566.html
sparks Hive Bee	posted 01-21-2000 06:25 AM That thread focus on the use of Pd and Pt and their salts. The thought was to avoid precious metals to cut back on the costs. About the nonpolarity, check this out: http://macweb.acs.usm.maine.edu/chemistry/newton/Chy251_253/Lectures/Solvents/Solvents.html They also list acetone and MEK as dipolar aprotic. But your right etAc wont mix well with the rest, but acetone sure will. The question is: is it a suitable solvent or will it interfere with the reaktion. If it's possible to use some more down to earth solvents i will run a micro scale test with anethole immediately. But i'm a bit low on anethole so i wont waste it unless someone can give me a little hint if it's worth trying with acetone.
Osmium PimpBee	posted 01-21-2000 06:42 AM You are talking about this one, right? http://rhodium.lycaeum.org/chemistry/guest.phenylacetone.txt I don't think that acetone will work. Several reasons: during the reaction either bromine or hypochloride is produced. Both will react with the acetone. And acetone isn't dipolar-aprotic either. But that's just my personal opinion, I'm not sure about it.
sparks Hive Bee	posted 01-21-2000 07:07 AM That's the one, Fester refers to it in his book too, i noticed. Actually acetone and ethylacetate was the two they used on the url. in my earlier post to illustrate typical dipolar aprotic solvents. But why would they react with acetone and not DMF,the point of attack would be the double bond i think, which they have in common. Now, if acetone wont work either there must be some less exotic solvent that can be used. The thought that comes to mind is how the wacker runs on meOH nowadays. I must do some thinking about what role the solvent plays in this oxidation.
CHEM GUY Hive Bee	posted 01-21-2000 02:40 PM Hummm, why not DMSO? It is very polar and aprotic. ------------------ Everything in this post is for informational purposes only, and is not intended to facilitate illegal activity. I've done nothing illegal and nor should you.
born_slippy Hive Bee	posted 01-22-2000 02:14 PM You can make LiI easily. Buy LiCO3 from a pottery shop and add HI to it.
sparks Hive Bee	posted 01-25-2000 03:54 AM Thanks for the info on LiI, I haven't given that much thought yet as this oxidation would only be interesting if it could be done with cheap solvents. Last time i checked the price on DMSO it was pretty high. It seems the only DMSO i can get is of extreme purity and therefor very expensive. On the other hand, DMSO and acetone structurally related (just a S instead of a C) so if acetone is unsuitable then probably DMSO is too.
Osmium PimpBee	posted 01-25-2000 04:58 AM DMSO and acetone might be structurally related on paper, but they are reacting differently. Why don't you give it a try with acetone? If it works you will be a hero, if it doesn't work, well, anethole isn't that expensive.
sparks Hive Bee	posted 01-26-2000 04:48 AM I checked the watersolubility for acetonitrile versus ethylacetate. Acetonitrile: miscible. 7.4g./100ml. Ethylacetate: moderately sol. 8g./100ml. Not much of a difference. But how will they differ when used as solvent/electrolyte? Acetonitrile was also said to be used as nonaqueous electrolyte for electrochemical cells. I don't know what to think, but DMF and acetonitrile seems to be two completely different animals but obviously both are useful as solvents in this oxidation. -Anyone out there who can straighten this out?
Osmium PimpBee	posted 01-26-2000 05:06 AM Only 7.4g/100ml? Are you sure about that?
sparks Hive Bee	posted 01-26-2000 05:21 AM According to chemfinder, yes. Looks like it's going to be a twophase system. I don't remember if it was supposed to be stirred or if the gasbubbles was the only agitation needed. I didn't think about what i wrote until now. I'll reread that text right now. But i'm sure about that solubility data.
sparks Hive Bee	posted 01-26-2000 04:23 PM Ok, first of all, don't ya all jump on me if i've got something wrong.....as i've had some to drink. But as i get it, the reactionmixture is an organic and an aquas phase. Check out the patent on rhodiums site. I'm not saying that i'm right, but i'm pretty sure ethylacetate will do as solvent. Well, give me some constructive chritisism! (I'm just a chemhack doin' what i can) (not really, i'm a renegade lowlevel chemteacher doin' what i can)
Osmium PimpBee	posted 01-27-2000 05:48 AM The patent on Rhods site mentions that after the reaction the two phases separate on their own. So indeed it seems to be a two-phase reaction, at least with the acetonitrile. It has to be stirred all the time BTW. The question remains: why did they use DMF and acetonitrile? Both solvents aren't uncommon, but more expensive than the standard solvents. Industrial chemists are tight asses, they save every buck they can. There must be a reason why they choose those solvents. I'd say go ahead, try it with ethylacetate or another solvent. It might work.
sparks Hive Bee	posted 01-27-2000 08:10 AM I'll try it this weekend if nothing else comes up (i'm pretty busy right now". I think i will use a cirkular arrangement of the electrodes with a stainless steel tube in the middle. That way i'm able to use overhead stirring through the tube (my mag. stirrer motor burned out last week). If this works it will really cut down the costs for making ketones. well, nothing's tried or proved yet.
Sploofer Hive Bee	posted 01-27-2000 09:26 PM why not pressurize and hydrate it all the rings and everything??? do ya think the info the goo dinfo can be related and relayed in a few lines ya are hoping for to much go read a book....
Sploofer Hive Bee	posted 01-27-2000 09:29 PM I think Id try vasoline first myself.....
sparks Hive Bee	posted 01-28-2000 01:35 PM Well, my first try didn't work out as expected. Don't ya all try to use a dremel to stir things, it's not such a good idea as it may seem. I'm not gonna tell you about it Now i'm goin' to take a deep dive into a bottle. i'll try again tomorrow. I'll keep you informed. And sploofer, if you was drunk- you're excused. If not- FUCK YOU and stay out of this thread. Or else i will make your life a living hell. This is a serious dicussion, and it doesn't need yuor kind of comments.
sparks Hive Bee	posted 01-28-2000 01:50 PM Well, sploofer i was thinking that i've said too much, but then i reread your post,and all i have to say is : FUCK YOU! What do you think? Do you think i'm some newbee or? Sorry all, i'll keep my mouth shut. Let's try to keep this on subject.
sparks Hive Bee	posted 01-28-2000 08:02 PM Shit, this has turned sour. I'll try my theories and post the results in a separate thread. Maybe i've got a bit of a short fuse, but that dickhead sploofer really pissed me off. sorry all, i'll try to not care so much what people write. But i'm a bit touchy when i drink.
Sploofer Hive Bee	posted 01-28-2000 10:14 PM fortunatly being dead is better than being scared in my opinion however the electro supplement is ussually investigated in to either very much simplyfy things or complex them however there are allways easier ways ussually the greqat invwestigative efforts and reports ussually are preformed because they the electro can do what is seemingly likely almost impossible it is possible to through these applications that new routes may be learned and simplicity eluted any of them process are concerned the ussual genera are quite simple to elute......
sparks Hive Bee	posted 01-29-2000 03:02 AM Well, we'll see later today if it works. If i can get some acceptable stirring of the reactionmixture. And sploofer, i was a bit drunk when i wrote that, so what do you say? Let's try to be friends from now on.

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