O2 Wacker Vs. Performic rxn. (Success and Ease)

[LiquidGaia]

I'm wondering which would be prefered someone who hasn't done an oxidation before.
The O2 wacker would provide for higher yields than the performic however the performic looks on the same level as the O2 wacker. I am interested in this because I found some nice oxygen bottle at the favorite orange home repair store.

Which method would be simpler with guarantee of moderate success?
thc...

[TheBlindGenius]

is much better IMHO, because you get higher yield and also it is less labor-intensive.  All you have to do is an extraction, a couple of washings, in the sep funnel, then dry and distill.  And you don't need much chemicals at all.  Just safrole, pdcl2, ethanol/methanol/IPA/DMF (whichever you choose), cucl2/cucl, dcm to extract, and some sort of drying agent.  that's it.  well, i guess it is labor intensive if you don't use a lab shaker.  but then again, if you have an oxygen tank, stirring may be sufficient if you don't skimp on the catalyst.  by the way, don't even think about using glass unless you're planning to use something like this



a glass pressure vessel setup can run you from $1,000 to $10,000+ depending on how big it is (usually less than 5 liters is available without being custom), who made it, what kind of pressure it holds (glass pressure vessels are made up to ~180 psi), if you want temperature control, cooling, heating, or even computer control, etc.  Big investment, but swim would do it if he had the money  

[LiquidGaia]

Swims' thinking about using the two liter bottle idea, but Swims' somewhat unsure about how I should go about rigging up the system. Also how much PdCl will Swim able to recover. Swim has 750g of ally-honey to work on and only 5g of PdCl.

[pupilage]

O2 wacker by all means. It is fairly straight forward. If you take your time with the extraction after rxn is complete you should be able to recover 80% or better of your pdcl. The two liter soda bottle works well. Swim has drilled a hole in the top of the cap and placed the valve through that using tire sealing cement to help add a better seal. Test your rig using IPA and pressurize it to 35 to 45 psi then shake hell out of it, if it is going to fail better it fail in the test stage and not when you have it loaded with oil.

[Antibody2]

O2 wackers would have been more fun if i had simply taken the money for reagents and flushed it down the toilet, then turned on the tv. Unless the idea of exp[loded wacker bottles, a house stinking of safrole and the notion of spending countless hours trying to aminate pretend ketone appeals to you.

performic on the other hand, may appear to be more work, but isn't because it is as reliable as the tide, you have to work very hard to fuck up the performic.

imho

[scram]

You'll be able to oxidize 660g of your oil with 5 grams. ~17 hours @ 45C

[TheBlindGenius]

what kind of setup was this?

[madprosr]

well, swim was having alot of trouble with apparent glycol contamination in the ketone from his performic runs. bad yields of ketone and bad yields aminating it...

being too lazy    to measure the density of his 6-month-old-unrefridgerated h2o2 he just picked up some fresh 35%.

he then reacted 24.7g iso + 4.85g Na2CO3 with performic prepared ala labtop, stirring for 24 hours. he separated the dcm, extracted the aqueous solution once more, and boiled off most of the dcm at atmospheric pressure. this was left to cool, then high vacuum was applied until the pump exhaust smelled like formic acid. yielded 34.6g of yellow oil, if pure that's a 98.9% yield of monoformyl glycol.

ritter was right on. Na2CO3 has the additional advantage over bicarb in that it doesn't foam up and force you to slow down the addition rate.

swim then rearranged the glycol for 3h with 60ml MeOH and 180g 15% h2so4 (drain cleaner) per 100mmol iso used. extracted, washed with bicarb, and distilled 20.2g ketone from 100-107C (peaking at 105C) with no column. the ketone shows none of the stickiness seen before. 74.4% molecular yield from iso.

swim had a bit of trouble forming the oxime from it, only small amounts would crystallize, the rest congealed and was scooped out. oxime looks like it will never dry... so swim is running a MeNH2/al/hg in the meantime, will know the yield soon.

IMHO the buffered performic with FRESH peroxide is a totally bomb-proof way to make several hundred grams of ketone in average sized glassware. i suppose the o2 wacker can do the same for you, but it has it's own tricks and limits you to how much you can shake.

[TheBlindGenius]

I would probably do the performic or peracetic instead of the Wacker if it wasn't for the extra step of converting the safrole to isosafrole.  Not only must the safrole-)isosafrole reaction be run, but then the isosafrole must be distilled.  And then you have two distillations after that.  So a total of three distillations, where with the Wacker, you must only do one.

[Vibrating_Lights]

with the performic

[Rhodium]

Gravity filtrations are slow, inefficient and generally obsolete. You can build a real vacuum filtration setup for as little as $25 with an aspirator, a polypropylene buchner funnel, a filtration flask and some rubber tubing. For $50 you can get a state-of-the-art vacuum filtration setup which will pay for itself in just a few days considering how much time you save.

[madprosr]

swim reacted 8.6g of ketone in a MeNH2/al/hg, basified to pH 12, extracted 5x 25ml toluene, washed 4x 25ml brine, and gassed out 6.9g of fluffy white mdma.hcl

long live the performic.

swim supposes if he fractionally distills the ketone next time and removes the forerun he might see even better yields and have less trouble forming the oxime... going to try using reagent grade H2SO4 and MeOH as well...

[raffike]

So a total of three distillations, where with the Wacker, you must only do one.

Raf usually double-distilles ketone so it makes total of 4 distillations and he's fan of buffered performic.I don't know about you but i love distilling,especially vacuum distillations.They are not time consuming yet easy when you have proper equipment.Safrole to isosafrole may be little more difficult to some bees,but Fe(CO)5/NaOH method might be worth looking into(in the matter of fact,raf ordered some Fe(CO)5 a week ago,it should arrive in 2 weeks,then he can post his opinion about it) as compilation at Rh claims 97% yields.

[Rhodium]

RuCl₃ isomerization sports a 95% conversion of reacted safrole to isosafrole at 130°C in a few hours, and I am confident that the catalyst can be re-used. It is far less toxic than Fe(CO)₅.

[scram]

Forget anything large scale with 02 wacker. You'll need to buy a heavy assed glass lined reactor which may not even provide enough agitation. A nice 10 liter pilot plant reactor would produce a nice amount. But is it worth $8000 or more? You'd probably get 90% yields if it had a heater on it.

[raffike]

It is far less toxic than Fe(CO)5
Is Fe(CO)5 really highly toxic?It's fairly cheap,that i know.Merck says something about liver and kidney damage but in fairly large doses.I think one should be fine if he handles it with care.97% yield is what attracts me most in this procedure and the reaction is very fast also.Fe(CO)5 is a liquid which dissolves in safrole,washing post rx mix with some diluted acid solution should destroy any remaining pentacarbonyl.

[Rhodium]

http://www.osha-slc.gov/dts/chemicalsampling/data/CH_247500.html

http://physchem.ox.ac.uk/MSDS/IR/iron_pentacarbonyl.html

[abolt]

Scram, why wouldn't a $300 60 psi 10 litre aluminium  pressure pot (used in spray painting) with a glass vessel (beaker) placed in it on a mag stirrer do the same job?

[scram]

I don't know. Have you tried that. I've thought about that but it seemed to me that they are not quite aluminum and thick & magnetic enough to prevent the stir bar from moving. Maybe unless you got an Ika. Let me in on a brand of paint pot that worked for you.

[becomezen]

You cannot run the O2 wacker in a metal container , as this will react with the Palladium , and shoot your yields down the drain (as well as your expensive PdCl2) ....

[scram]

No shit Sherlock. Thanks for pointing out the obvious. That's what a paint liner is for.