Author Topic: possible problems with 1st buffered performic  (Read 4793 times)

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bbeeasheets

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possible problems with 1st buffered performic
« on: September 12, 2004, 10:15:00 AM »
well, my lab skills suck so far, but muddling my way thru. after distilling safrole, isomerization and distilling isosafrole twice, i started my first buffered performic using OcoteaCymbarum's excellent writeup for newbies. everything went fine with first addition of performic, however during second addition, my reflux apparatus sprung a leak, and as i wasn't watching it very closely and it was under a hood, all the dcm boiled out. and the mix reached about 95C. is this temp high enough to cause side reactions and polymerizations to occur? i am going thru with the acid hyrolosis anyway, but would like to have a heads up on what to expect.


thanks

DoctorFeelgood

  • Guest
95 C ???
« Reply #1 on: September 12, 2004, 03:05:00 PM »
95 degrees C is far too much. we use DCM, because it has a low bp (40C). this reaction should never go to 95C ! the addition of the formic acid is a critical part of the reaction, never walk away, you have to control the temp with the addition rate. if all the DCM has boiled off, what do you want to separate and hydrolize ? i never had this problem, but it sounds not good to me. you can try to add some DCM for extraction, but don't know if this will work after the reaction has finished.

bbeeasheets

  • Guest
does a positive bisulfite test on distilled...
« Reply #2 on: September 13, 2004, 09:18:00 AM »
does a positive bisulfite test on distilled mdp2p? mean that the reaction went ok even if i messed up and let temp go up to 95C or can there be other ketones that will give a positive? possible side products?

DoctorFeelgood

  • Guest
please clarify
« Reply #3 on: September 13, 2004, 11:28:00 AM »
if you need help. what did you do exactly. a positive bisulfite test sounds good. did you hydrolize something or what did you do?

bbeeasheets

  • Guest
to clarify
« Reply #4 on: September 13, 2004, 12:40:00 PM »
ist ever hopefull mdma synth. fractional distilled safrole, isomerized with KOH, fractional distilled iso-saf. attempted buffered performic using OcoteaCymbarum's excellent writeup for newbies. reflux apparatus (rubber stopper in 3 neck flask which i do not have an adapter for) sprung a leak.. ie cork poped out while i was having a smoke outside (i know... stupid ass newbie fuck leaving first time reaction alone!) and the dcm quickly distilled off and mix got up to about 95C) i quickly cooled it down to about 60C and added dcm so it was refluxing smoothly thru the rest of second addition of performic. the rest was continued as stated and workup was performed exactly as stated. what i noticed was the colors were darker than OcoteaCymbarum's pictorial. especially the glycol. as per abolt's reply, after distilling dcm for 2 hours, i added weak vaccuum and about 30mls more came over. i set dcm aside to see if the 30mls was really dcm. the glycol at room temp was almost blak and thick like honey, was slightly red when held up to light. here was a very clear difference. OcoteaCymbarum's is definatly red, doesnt look near as viscous  and is somewhat translucent. my yield was 365gr glycol, from 300gr of iso. i then went though hydrolosis as stated, and everything went as planned, except color was again different. final (hopefully raw ketone after washes and drying was dark brown. distilled and collected fraction that boiled at 40C above my safrole distill. (200C-206C) i stopped here for fear of polymerization. ketone? was yellow with hints of green and blue. did a bisulfite test and the whloe tube crystallized with some fatty shit on top. i guess my question is... is bisulfite test enough to ensure that i have mdp2p or could it still be some other ketone?

abolt

  • Guest
My 2004 Darwin award nominee
« Reply #5 on: September 13, 2004, 11:29:00 PM »
reflux apparatus (rubber stopper in 3 neck flask which i do not have an adapter for) sprung a leak.. ie cork poped out while i was having a smoke outside (i know... stupid ass newbie fuck leaving first time reaction alone!) and the dcm quickly distilled off and mix got up to about 95C)

A "fixed cork" is not a "reflux apparatus".

Here is a picture of a reflux apparatus:



Breathing DCM fumes can KILL YOU.

Inhalation - Dizziness. Drowsiness. Headache. Nausea. Weakness. Unconsciousness. Death.

http://www.cdc.gov/niosh/ipcsneng/neng0058.html


 

Peracids can EXPLODE when heated to 110 Celcius and over.

Flammability and Explosibility Peracetic acid explodes when heated to 110 °C, and the pure compound is extremely shock sensitive. Virtually all peracids are strong oxidizing agents and decompose explosively on heating. Moreover, most peracids are highly flammable and can accelerate the combustion of other flammable materials if present in a fire. Fires involving peracetic acid can be fought with water, dry chemical, or halon extinguishers. Containers of peracetic acid heated in a fire may explode.

http://www.hhmi.org/research/labsafe/lcss/lcss68.html


 

i quickly cooled it down to about 60C and added dcm so it was refluxing smoothly thru the rest of second addition of performic.

How was it refluxing? DCM has a boiling point of 39 Celcius, so without some type of condensing, it would have evaporated into the atmosphere again.

Did you have all the necks sealed?

especially the glycol. as per abolt's reply, after distilling dcm for 2 hours, i added weak vaccuum and about 30mls more came over. i set dcm aside to see if the 30mls was really dcm. the glycol at room temp was almost blak and thick like honey, was slightly red when held up to light. here was a very clear difference.

You have toasted your reaction.

did a bisulfite test and the whloe tube crystallized with some fatty shit on top. i guess my question is... is bisulfite test enough to ensure that i have mdp2p or could it still be some other ketone?

I would be surprised if you had anything useful. UTFSE for the words "chicken fat".

Dude, don't take this the wrong way, but you have at least several months more reading to do. Please don't kill yourself.


DoctorFeelgood

  • Guest
try to aminate
« Reply #6 on: September 14, 2004, 01:23:00 PM »
a small sample, then you will see if it was mdp2p or not. keep abolt's notes in mind. some vapours are highly toxic, normally one has to evacuate the lab in this case. also read LabTop's writeup about the buffered performic - he writes about some of the critical parts too, e.g. formicacid can turn into a nice homemade bomb...
i would recommend reading more about this synth. it seems that you did not fully catch the critical parts, which could lead to big problems for your health, which is sure not what you want.
i can also recommend doing a smaller batch before doing a full 300g iso batch. i allways do a testbatch with e.g. 1/4 of the written amount, when trying out a new synth.
hopefully you got something useful, best wishes and good luck,
DF

placebo

  • Guest
SWIM have had one that was jet black and ...
« Reply #7 on: September 15, 2004, 02:09:00 AM »
SWIM have had one that was jet black and worked fine. If you distilled and it looked good, and did the bisulphite test and it looked good then aminate. But to save your ass do as DFG said and split the amination into smaller ones, if it's a large amount for you.
I think it'll be fine.


DoctorFeelgood

  • Guest
KOH residue
« Reply #8 on: September 15, 2004, 12:43:00 PM »
Hi guys! After isomerization with koh pellets one distills out the iso - no problem.  My question is: what is the best way to remove the dark dirty koh residue in the distilling flask ?
thanx in advance
DF

abacus

  • Guest
water
« Reply #9 on: September 16, 2004, 02:52:00 AM »
Add hot water, soak for a while, rinse out.

Eventually you will get all the residue out without having to waste other chems or solvents. 

Abacus

DoctorFeelgood

  • Guest
hot water removes
« Reply #10 on: September 17, 2004, 06:04:00 AM »
all the dark shit, but something else is left which i can not remove, even soaking with concentrated H2SO4 could not remove this. Any idea ? If not, no problem, then i will use this flask only for isomerizations in the future.

amine

  • Guest
Ice water for condenser
« Reply #11 on: September 17, 2004, 01:33:00 PM »
From experience when working with dcm, distilling, refluxing etc...etc Swim highly recommend that you use ice cold water in your condenser, get yourself a nice aqurium pump, attach it to the condenser and make a reseviour(pardon my spelling) then run both hoses to the water, get plenty of ice,  and make a trap at the top of your condenser, generally Swim has a tube attached which goes into a beaker with ice cold water that way most of the dcm vapors say out of the air and away from your lungs.

DCM exposure will give you a headache like none other and breathing too much of it will knock you off your feet.

Anyway, please becareful, this thread is scary, its a good thing nothing bad happened. As for your yields I am sure you did get product however there might have been lots of side reactions taking place.

Generally swim keeps check on his reaction during the additoin process. 

Another tip, if you add your performic solution to fast to the isoalkene, and you feel you're about make a nice acidic water cannon, turn your stirrer off for a little while
or at least slow it down, it will slow down the reaction and  you won't have to deal with the clean up of acid everwhere in which case baking soda is your best friends for acid spills.

Don't give up your almost there.


Doc. I recommend boiling water to remove the tar that was formed, next time you run your isomerization try to keep the temp. around 120-140C and you won't have much formed.

What you can do is post isomerization is vacuum filter the oil and remove some of that KOH before you go ahead and do your distillation.


bbeeasheets

  • Guest
ok i lived
« Reply #12 on: September 18, 2004, 03:39:00 PM »
well i really didnt know that dcm fumes were that toxic. i did have quite a headache for about 2 days.

abolt, i mistated what my reflux app was. it is exactly like yours posted, but my 2L is a 3 neck with a middle 45/50 joint that I don't have a reflux column for or adapter. i do however have a proper reflux condenser that was mounted in one of the side necks and a pressure equalized funnel in the other. the middle neck was stoppered, but when i stupidly stepped out for a smoke, it broke the seal. didnt pop out as there was really no pressure built up, but rose enuff from its seat to let the dcm escape, and of course the temp rose very quickly as the dcm escaped into my lungs!. damn i didnt know that this peracid would explode at 110C. no notes of that in the newbie writeup. very lucky i guess. anyways very little frightens me (stupid like that i guess). so i ordered a proper 3neck 2L rbf with all 24/40 necks for the next, hopefully clean, performic.

thanks for all the tips. i am going to try amination this weekend.

methyl_ethyl

  • Guest
Re: your almost there
« Reply #13 on: September 18, 2004, 05:31:00 PM »
well i really didnt know that dcm fumes were that toxic

damn i didnt know that this peracid would explode at 110C.


Well babe, you should probably gain a better working knowledge regarding the chemicals that you are working with. It is quite well known that DCM is extremely toxic.

And please correct me if I am wrong but I believe 110C is the explosive threshold for peracetic acid not performic acid.  Although I am not a chemist and can not confirm that without the help of the great ones.  I am not sure at what temp performic will become explosive, this is the route you are using correct performic oxidation?


EDIT:Ok, I read the whole thread and realize where you got your 110C explosion figure from, and it seems abolt's post clearly states peracetic acid as the peracid defined with that limit.  I personally do not see why performic acid would have such a low explosion limit however I could be wrong.  The post claims that most peracids have low explosive limits.  Again a question for chemists, I am intrigued however at what point performic acid becomes explosive  :)  Anyone?

regards,

m_e


amine

  • Guest
MSDS
« Reply #14 on: September 19, 2004, 10:41:00 AM »
Its always a good idea to see what chemical you are going to be working worth and possible health hazards come along with it, all it takes is a quick google search to find it.


Sedrick

  • Guest
Yeah, sounds a bit yucky.
« Reply #15 on: September 19, 2004, 11:13:00 AM »