Possible Peracetic Revision

[PoohBear4Ever]

Already been asked, but I feel this topic could use a thread to itself:

MW: H2O2(34g); C2H4O2(60g); isostuffrole(162.12g).

1mol H202 + 1mol C2H4O2 ---H2SO4---> 1mol C2H4O3 + 1mol H20

So, if using 30% solution of H2O2 (1.11g H2O2/2.6g H20), we would need 110ml (30ml H2O2/80ml H2O). 

Now we have: 110ml H2O(30%) + 60g C2H4O2 ---> 76g C2H4O3.

The second oxidation goes:

1mol C2H4O3 + 1mol isostuffrole ---> 1mol stuffone.

So, the lesson learned here, only applicable if we lived in a perferct world, would be that for every 162g isostuffrole, you should use 110ml H2O2(30%) with 60g GAA, which is ~ 60ml. For every 100g stuffrole, we would need 68ml H2O2 with 37ml GAA.

It seems 1% catalyst suggested, but is this percent by weight or volume? Would assume weight, so it would be 1.2g per 114g GAA+H2O2, or 0.7 ml, correct? 

Here's the experimental (GAA/H2O2 + 0.33%; H2SO4 + 100%):

180ml H2O2 (30%) added slowly (~15min) to 100ml GAA, with 3ml H2SO4.  After stirring for 16hr, solution was slowly neutralized with 10g sodium bicarbonate. Next, 200g isostuffrone in 350ml DCM was slowly added to flask, and allowed to stir for 16hr. 

Semtexium, if we choose to use acetone instead of DCM, what do you think of the GAA/H2O2 ratios?  goiterjoe stated to me in a PM that Rhodium seems to have used Ritter's performic ratio in chems.  He also stated that Ritter seems to look more for a resulting product than for a perfect equation when synthing. 

When adding sodium bicarbonate, would it be best to add excess, making the solution basic, or just enough to neutralize?

A perfect ratio suggestion would gladly be tested by SWIP personally, and the results reported.  Perhaps not enough H2O2 was used in the past, resulting in not enough peracetic acid being formed in the first place.

Watcha think?

PB


*Also, could someone tell me what size stir bar is used for a 1L RBF when distilling/isomerizing?

[Chromic]

I can't find a reference to a successful HOOAc rxn using so little GAA. And, is anyone sure that H2SO4 is actually needed? Btw, seach Organic Synthesis on how much NaHCO3 to use. Your ideas look promising, report back how it goes. Btw, a 1.5" stir bar should suffice.

[PoohBear4Ever]

Already got that (NaCHO3) figured out the hard way:

  NaC2H3O2= 72g/mol 
  NaHCO3=   82g/mol 
  H2SO4=    98g/ml   SD=1.8

Soooo,  if using 5 ml sulfuric (93-95%), you would have 9g, or ~ 0.091 mol. Multiply this by 2 and get 0.182, which is what you want of the NaHCO3 or NaH3C2O2. This amount to 15g baking soda, which is 15% more of the 13g of sodium acetate necessary to aceive this. 


Well, guess it could likely be why manufacturers decide to sell their peracetic acid solutions with acetic acid (H2O2 as well).  I'll just use the maximum amount my rxn vessel allows to ensure proper oxidation, but what about the H2O2 amount?  This would be if we wanted to convert all the acectic acid, but do we really want to...

PB

*Yes, sulfuric is needed as a catalyst, and I've seen several other sources that say so.

[Chromic]

H2O2 + HOAc <==> HOOAc + H2O.

It's an equilibrium reaction. I'd use 2mol of HOAc, 1mol H2O2, 1wt% H2SO4 to get your 1mol HOOAc. Looks like sulfuric acid is pretty common catalyst in preparing HOOAc. (just checked)

[PoohBear4Ever]

When we add the catalyst into the equilibrium, how much would it shift it to the right? Using you molar suggestion would just about make it a 1:1 ratio.

Checking around, it seems 40% peracetic solution is most common, so I'll assume this is what we want for out oxidation.  Using the above ratio, this is ust about what we would expect.


New Experimental:  Use goiterjoe's ratios, cuz doing the above comes out to just about that. He would have 2:1 ratio for peracetic, and enough acetic left over, and water created, to make a 40% solution.

Sorry for the waste of time,

PB

[Chromic]

Ok, I've got a better answer:

Shulgin says 34g 30% H2O2 (10.2g H2O2), 32.4g iso. Buffered performic uses 550ml DCM/230g iso (although Semtex uses 500ml acetone/325g iso). So I'd have to recommend that you use:

32.4g iso (0.2mol) in 50-80ml dcm

34g 30% H2O2 (0.3mol)
36g HOAc (0.6mol)
0.5g H2SO4 (1wt% of the mass of H2O2+HOAc)

I can't help you with buffering as this is definitely uncharted realms and it would likely introduce too many variables. You're already using 1/5 the amount of GAA that Semtex used, and substituting DCM for acetone. I know both of these things are minor variables, but I'd try this first and report back.

I'm tempted to avoid GJ's asarone writeup as he never checked his product with bisulfite or aminated.

[Chromic]

This definitely isn't a waste of time, please give a good writeup.  

[PoohBear4Ever]

Cool, thanks.  I'll be using acetone instead of DCM (forgot to change in post), cuz Semtexium stated that the ketone didn't act right in the freezer (getting thick when it should stay free-flowing liquid). 

PB

BTW, the ratios you gave will create a 40.05% peracetic acid solution.  These are the numbers:

340g iso
375ml acetone

300ml H2O2
280ml GAA
3ml H2SO4 (1.9%)

Would slim it down some more, but SWIP thinks this is a good place to start. Hope it all goes well, and fits in a 2L flask.

[PoohBear4Ever]

How about the buffering?  What side rxns could possibly take place?  Could the peracetic react instead of only the sulfuric?  Would the sulfuric damage the isosafrole if left in?  Does a basic solution give higher yields than an acetic one?

PB

* Is a 40% peracetic solution too high?

[Semtexium]

Please keep in mind that the peracetic with acetone is likely to produce acetone peroxide which is a sensitive primary explosive!!!  SWIM's never had any problems with anything blowing up, but has noticed in the past some xtals forming in the ketone distillate and in the condenser which could have been acetone peroxide.  I think ethyl acetate has been mentioned as a possible substitute, SWIM doesn't have any at the moment so has been unable to try it out...

This warning WAS in the writeup on Rhod's page which has been changed/removed with the peracid review...
            Mean People Suck             

[PoohBear4Ever]

Shit, damn it, fuck!

Back to the proverbial drawing board.  What's the chance of all the H2O2 not reacting with the GAA, and could one simply use dilute acetic acid solution for addition?  What about MeOH, like in the animation? 

PB


* Semtexium:  Being as knowledgable as you are on the subject, what tips have you to offer for someone attempting this synth? Any would help.

[Chromic]

I'd use DCM as all of the refs that I've read use. Btw, dilute H2SO4 won't hurt iso. You'll flood and extract with DCM anyways...

[foxy2]

I would try useing that acetone peroxide aka(dimethyldiroxane) to form the epoxide.  The literature says quantatative yeild if i remember correct.


Do Your Part To Win The War

[Rhodium]

Poohbear: A catalyst does not shift a reaction equilibrium, it just makes a mixture REACH equilibrium faster. I believe the HOAc + H2O2 => peracetic reaction is far to the right.

Foxy2: The explosive acetone peroxide is a cyclic trimer of dimethyldioxirane, and it detonates/deflagrates when scratching a few crystals under your shoe against a cement floor.

[Semtexium]

DO NOT use the Goiterjoe writeup, I have confirmation that what comes out of it is NOT ketone, it does NOT aminate, it's looking very similar to a run that was once tried, a modified buffered peracetic.  It gels up in the freezer, but comes over at the same temp as ketone would...  Back to the drawing board...  
            Mean People Suck             

[Semtexium]

Hey Rhod, didn't you mention in the past that you thought the rxn could proceed without acetone, as the GAA would possibly act as solvent enough...?
            Mean People Suck             

[Rhodium]

Yes I did, the acetone is probably not necessary.

[Chromic]

Foxy, DMDO cannot be formed in situ.

Semtex, a buffered peracetic will work, just no one has done it. There's no risk of acetone peroxide, if anything DMDO would form, but the isosafrole epoxide/glycol is much more energetically favored.

Rhodium is right on the money as usual.

[Semtexium]

Rest assured that if I didn't think the modified peracetic would work I certainly wouldn't be getting SWIM to keep on trying.  Fact of the matter is that I have no doubt it can be made to work, as I have no doubt that the MDP2Pol route can be made to work given enough trial and error.  What I was pointing out was that the writeup given by Goiterjoe does NOT yeild ketone, that's all...
            Mean People Suck             

[PoohBear4Ever]

Because this bee would prefer not to leave himself open to possible detonation on his first dream of this type, could one of you more knowledgable bees suggest some numbers for this larva to use in his dream?  The only limit would bee his 2L flask, and he would prefer to have maximum ketone potential to be a factor.  After acheiving his isostuffrole, he will test acetic acid's suitability as a solvent, though having a backup idea would really be helpful. 

How many moles of peracetic acid would one desire to oxidize one mole of isostuffrole? 

Thanks,

PB

* Also, if peracetic acid is more more basic than performic, is there really any advantage if buffered, or is the sulfuric acid the reason why it would be favored to do so?