Author Topic: Old Classic Performic  (Read 2161 times)

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guyincognito

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Old Classic Performic
« on: July 08, 2002, 10:43:00 PM »
Swim wants to run an old acetone performic to make md-p2p to compare against results (quality of md-p2p) getting from new modified performic (DCM) but cant find on hive the method used to use (just tid-bits).

It was in TS 2 and the method swim used didn't use diethyl ether in it to extract.

Anyone know the details of the recipe?

Osmium

  • Guest
PIHKAL
« Reply #1 on: July 08, 2002, 10:49:00 PM »

http://www.erowid.org/library/books_online/pihkal/pihkal109.shtml



You can greatly reduce (or even completely leave out) the acetone and process bigger amounts as long as you are careful with the iso addition and use good stirring.

I'm not fat just horizontally disproportionate.

guyincognito

  • Guest
thanks osmium, by careful you mean - add the iso ...
« Reply #2 on: July 08, 2002, 11:50:00 PM »
thanks osmium,

by careful you mean - add the iso slowly (while keeping the temp below 40 C?  (or should it be 20 C)?

guyincognito

  • Guest
It says extract with 3 times 75 mls Et20, Can DCM ...
« Reply #3 on: July 09, 2002, 12:00:00 AM »
It says extract with 3 times 75 mls Et20,

Can DCM be substituted? swim doesn't like ether.

and is the 60 mls methanol in the hydrolysis neccesary?  (swim remembers discussion about that, but not the result)



from 3,4-methylenedioxyphenylacetone) This key intermediate to all of the MD-series can be made from either isosafrole, or from piperonal via 1-(3,4-methylenedioxyphenyl)-2-nitropropene. To a well stirred solution of 34 g of 30% hydrogen peroxide in 150 g 80% formic acid there was added, dropwise, a solution of 32.4 g isosafrole in 120 mL acetone at a rate that kept the reaction mixture from exceeding 40 ° C. This required a bit over 1 h, and external cooling was used as necessary. Stirring was continued for 16 h, and care was taken that the slow exothermic reaction did not cause excess heating. An external bath with running water worked well. During this time the solution progressed from an orange color to a deep red. All volatile components were removed under vacuum which yielded some 60 g of a very deep red residue. This was dissolved in 60 mL of MeOH, treated with 360 mL of 15% H2SO4, and heated for 3 h on the steam bath. After cooling, the reaction mixture was extracted with 3x75 mL Et2O, the pooled extracts washed first with H2O and then with dilute NaOH, and the solvent removed under vacuum The residue was distilled (at 2.0 mm/108-112 ° C, or at about 160 ° C at the water pump) to provide 20.6 g of 3,4-methylenedioxyphenylacetone as a pale yellow oil. The oxime (from hydroxylamine) had a mp of 85-88 ° C. The semicarbazone had a mp of 162-163 ° C.

goiterjoe

  • Guest
DCM will work
« Reply #4 on: July 09, 2002, 12:20:00 AM »
DCM will work for your ketone extraction.  You might want to use more DCM than it calls for though, as the solubility seems to be slightly lower.

I once was performing an acid hydrolysis on some post oxone epoxide and realized I only had a fourth as much methanol as I needed to complete the reaction.  I figured what the hell, it didn't seem to make that much of a difference how much I used, just as long as it kept the reflux temperature down.  After 3 hours of refluxing, the product was worked up and fractionally distilled.  The largest fraction by far was the glycol!   I ended up breaking down and driving out to the store to pick up some more methanol.  The glycol hydrolyzed into the ketone fine the second time using the proper amount of methanol.  Whether this will hold true for the classic performic is another story.  It might work without as much methanol, but I wouldn't risk it.

All paths are the same: they lead nowhere

baalchemist

  • Guest
Hydrolysis doesnt need MeOH to work.
« Reply #5 on: July 12, 2002, 10:30:00 AM »
Hydrolysis doesnt need MeOH to work. Baal has'nt used MeOH in years. Try a 2 hour hydrolysis @80c instead. 3 hours is way too long, it greatly reduces the potential yields.

    GODISNOWHERE
Shoot Narcs, Not Drugs

Osmium

  • Guest
> Try a 2 hour hydrolysis @80c instead.
« Reply #6 on: July 12, 2002, 12:56:00 PM »
> Try a 2 hour hydrolysis @80c instead. 3 hours is way too
> long, it greatly reduces the potential yields.

It depends how big your hydrolysis is. A real big one might take quite some time to heat up and cool down and that time of course has to be counted as reaction time too. The stirring mode is also important. It's no problem to stir a small reaction, but when you have several liters and a liter of black tar sitting in the bottom of your reaction vessel heated by a strong mantle then reaction times might vary. So it depends how you define reaction time. I've had better results with longer reflux times.


I'm not fat just horizontally disproportionate.

OB1KNoBee

  • Guest
OXONE runs
« Reply #7 on: July 12, 2002, 01:57:00 PM »
Osmium,
 Are you speaking of the oxone runs/ isosafrole-->epoxide->ketone?

If so, were your yields any good ?

GOOD GOOD

Osmium

  • Guest
No, the classical performic. Yields 60%.
« Reply #8 on: July 12, 2002, 03:44:00 PM »
No, the classical performic. Yields 60%.

I'm not fat just horizontally disproportionate.

guyincognito

  • Guest
Baalchemist, So no methanol is fine in the ...
« Reply #9 on: July 16, 2002, 09:23:00 PM »
Baalchemist,

So no methanol is fine in the classic performic (acetone) method?

As well - should the Temp be kept below 40 C or 20 C when adding the iso/acetone to the performic??


noj

  • Guest
preheating
« Reply #10 on: July 17, 2002, 06:38:00 PM »
A real big one might take quite some time to heat up and cool down and that time of course has to be counted as reaction time too

I thought the standard practice was to preheat the dilute H2SO4 to 80°C before adding the epoxide. When you do, 2hrs works. Afterwards, you can add ice cold water to help it cool down faster.

there's a big difference between criticizing your government and criticizing your country

guyincognito

  • Guest
Thats a good question: after the 2 hour ...
« Reply #11 on: July 30, 2002, 04:33:00 AM »
Thats a good question:

after the 2 hour hydrolysis - should it be ice bathed to bring it back to room temp?  or left to cool while stirring?

Wouldn't there still be a reaction going on for hours after while it cools if it isn't ice bathed? (swims takes at least 4 or more hours to cool down on its own)



baalchemist

  • Guest
Baal floods the reaction after 2 hrs with ice ...
« Reply #12 on: August 02, 2002, 06:13:00 PM »
Baal floods the reaction after 2 hrs with ice cold H2O while stirring, within a few mins its ready to extract. It only needs to be cooled enough as to not boil off your extraction solvent(DCM). Osmium brought up a good point on hydrolysis times, on runs larger than ~750g, Baal has found that add'l time may be required. It depends on the amount of H2SO4 used in scaling up. I say this because less H2SO4(than the standard formula) can be used on large runs to aid in reducing the reactions volume. If that be the case, time must be adjusted.
Example: Typically Baal would use 2500ml-15%H2SO4 for a 250g run @2hrs. When running a 1kg reaction, 10,000ml of H2SO4 would be needed according to the above formula. Baal uses a 10k-ml flask for this, so the H2SO4 amount will be cut back accordingly to allow it to all fit into the flask. This would require more than 2 hours because of the scale and adjustments.

    GODISNOWHERE
Shoot Narcs, Not Drugs

Flip

  • Guest
But for the rest of us......... (below 750)
« Reply #13 on: August 02, 2002, 10:17:00 PM »
Too long, too hot, too bad

WARNING - DO NOT TAKE THIS PERSON SERIOUSLY.  NO, SERIOUSLY THOUGH.

guyincognito

  • Guest
ok baal, what would the rxn time be for 3000mls ...
« Reply #14 on: August 07, 2002, 03:40:00 AM »
ok baal,

what would the rxn time be for 3000mls of iso?

and how much 15% sulfuric would you use?

someone said they reflux it?  Would that be the same as 80 C?

Osmium

  • Guest
If someone wants to do a 3l reaction, then they ...
« Reply #15 on: August 07, 2002, 01:12:00 PM »
If someone wants to do a 3l reaction, then they should consider scaling up SLOWLY (like by 2 or 3, not by 10 or so) and figure it out themselves. Can't hurt to invest 20 bucks in TLC plates and check the composition of the reaction while it is running. 20 bucks are nothing compared to a flask containing several ten thousand dollars worth of drugs!

I'm not fat just horizontally disproportionate.

guyincognito

  • Guest
call swim stupid, but what is a TLC plate and how ...
« Reply #16 on: August 10, 2002, 11:25:00 PM »
call swim stupid, but what is a TLC plate and how would one use it?

Rhodium

  • Guest
UTFSE!
« Reply #17 on: August 10, 2002, 11:35:00 PM »