Author Topic: Is the minimum temp 120C?  (Read 10023 times)

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  • Guest
Is the minimum temp 120C?
« on: December 30, 2003, 02:17:00 PM »
I noticed when reading this document

on Rhodiums site the following sentence.

Actually, hydriodic acid dissociates by a reversible reaction at high temperature (120°C) to iodine and hydrogen which is the reducing reagent.

Does this mean that the minimum temperature in the HI synthesis's is 120C?


  • Guest
Azeotropic B.P
« Reply #1 on: December 30, 2003, 04:32:00 PM »

57% HI SOLUTION (HYDRIODIC ACID) : B.p 125.5-126.5 deg C/760mm Hg ;Density 1.70 gr/ml ;  55-57%  w/w HI is 0.936 to 0.99  grams of HI per ml.

Minimum temperature in the HI synthesis is B.P 125.5-126.5 deg C/760mm Hg


  • Guest
Thanks Wizardx,
« Reply #2 on: December 30, 2003, 10:19:00 PM »
But how is it that many bees claim to keep the temp at 100C with good results.  Does a longer rxn time compensate for the lower temp?

I have always assumed that a longer rxn could bee carried out at a lower temperature.  However, that sentence, gives me the impression that unless the temp reaches 120C then the HI is not being used to its potential.


  • Guest
time vs. temp
« Reply #3 on: December 30, 2003, 10:24:00 PM »
Does a longer rxn time compensate for the lower temp?

Yes, to a certain extent, but likely not fully.

However, that sentence, gives me the impression that unless the temp reaches 120C then the HI is not being used to its potential.

That is definitely included in my belief system too.


  • Guest
Think of it like Congress
« Reply #4 on: December 31, 2003, 12:30:00 AM »
There are some things we may prefer not operate at their full potential. Congress comes to mind right away. Local law enforcement is another institution I have no interest in being operated at its full potential. The Jehovah's Witnesses, Al Sharpton, and George Bush are a few thing I hope never operate up to potential. A friend's car is capable of speeds in excess of 150 mph. He best not operate the vehicle to its full potential, because he had too few points left on his license right now. HI might be another thing that really needn't be used at its maximum potential.

I'm only half joking, and I know none of the analogies are chemistry analogies.

I noticed long ago there was direct correlation between hot cooks and tweaky dope. I learned later that part of tweak is the result of the dry-hot-fast start. Not all of it. Most of the more notorious by-product side effects-- the real tweaker stuff--is produced in hot cooks. Black helicopters, shooting sparks, faces in the woods, voices in the air ducts, people talking outside the fourth floor windows... all seem tied to hot cooks. How hot is hot? Hot is hotter than 120C. Even at 120, some tweaker characteristics start showing up.

At one point, I noted the temperature of the reactions I did to determine the effect of temperature on tweaker characteristics. As them temps went down in my admittedly drier and shorter push-pull type cooks, the tweaker effects dropped out. Sparks disappeared first, helicopters next, then the faces in the woods and general paranoia disappeared (at least until sleep deprivation supplied the effects.) The voices and shadow peeps all took leave of my dope in the range under 120C. Around 120C or a little above, the product would have tweaky effects. Below the 120 mark, there were fewer such problems, and the problems disappeared as the temperature fell to the 100C range. Doing a number of six hour cooks that were still too dry, I concluded that quality meth could be produced in reactions done below 100C which would not have the tweaker characteristics. I learned that if I increased the temperature to the 110-115C range, the tweaky effects began recurring, and any temperature higher than 120 seemed to guarantee such effects. 

I finally listened to reason and did a wet reflux, then a long wet reflux, then did one with no noticeable activity to start, no real show or smoke or drama. Just a wet reflux for 36 hours or 48 hours, at an easy, just below 100C temperature. The product of such a reaction done with clean pseudoephedrine is superb. The product lacks any adverse tweaker characteristics. It can produced consistently at this quality without difficulty and without a great deal of experience. Low temperature is one key to the quality and absence of unwanted side effects.

I have not duplicated the side effect experiments doing the long wet reflux, as I frankly have had no reason to repeat them. A 100C temperature produces meth that is as good as it gets with the red phosphorous method.

I started doing hypo synths, and learned quickly to keep the temperature low for that synth. I did not reflux for several hours while doing those, but concentrated the hypo and did a slash and burn fast reduction that was remarkably complete compared to my red phos reactions at the time. I never did the hypo synth as high as 120C without having a phosphine fire at some point.

When I started doing the phosphorous acid synth, I was using a deep fat fryer that would not bring the temperature in the flask to 120C at it hottest setting. The maximum temperature I could attain was 115C. Yet the product was unmistakably excellent. I noticed, however, that even with a longer reflux, temperatures lower than 110C did not give me the quality of product that I obtained at 115, and finally 120C. I changed heat sources and refluxed the phos acid reaction twelve hours at 120C; I was delighted with the results. I had very good product and an excellent yield. My most recent phosphorous acid reaction was done with with very well cleaned freebase pseudo at the higher temperature range, measured by the hot plate settings and the observed activity in the flask. I did not set a thermometer up to test, as I have-- once again-- broken all of them. The last reaction yielded meth that was as good as any I have produced in the last year. No tweak. Solid meth. Clean, smooth, and effective.

I am of the opinion that the phosphorous acid synth does its best work in the 120C range. I am not so inclined with the hypo synth, but my opinions there are tied to instances of phosphine fires. As to the red phosphorous method, at least for the long wet reflux done with actually clean pseudo, I believe that a 120C temp might be an optimal temp. I also believe that unless the pseudo is very clean (and I am of the opinion that very few cooks actually have very clean pseudo) a red phos cook done above 110-115C is an invitation to tweaker dope. Make the red phos reaction a drier push-pull reaction, and 120C guarantees tweaky characteristics. At least in my experience.

Maybe the fact that the typical clandestine meth cook is done with less that perfect precursors under less than optimal conditions mitigates against pushing the temperature of the red phos reaction to the optimal range. This observation could be a misunderstanding of what I have observed over time doing these synths. I belive the tweaky street dope is like that partially because the feedstock pseudo is not as clean as the cook thinks. The balance of the tweaker characteristics are, in my opinon, realted to the temperature of the cook. The STE, STB, and Tetra trap methods, as well as the EGull and derivatives, do not routinely yield completely clean pseudo feedstock. There has to be some workup beyond the base techniques with most OTC pseudo sources.  The pseudo obtained by faster extraction methods will react pretty well, but will usually contain something in addition to pseudo. Few street cooks clean the pseudo to an actually clean state. I know a number of bees who have never really gotten pseudo all the way clean, and who would likely not recognize really clean pseudo when they saw it. The pseudo's purity must be considered when you mull running the HI reaction at its maximum potential.

If you admit that most of the synths, and in particular the red phosphorous synths, are done in less than ideal conditions with less-than-pure precursors, cranking the heat up to 120C to optimize the HI may very well do nothing of benefit to the product made by these cooks. It may be better to back off ten or fifteen or twenty degrees, take more time, and be patient. I for one will likely continue to do red phosphorous reactions under the 120C mark, and will do the phosphorous acid cooks at the 120C mark. I do that based on my experience doing these synths, and evaluating the product produced.

It could easily be true that the clandestine cook does not really want to do this reaction at its optimum potential. That may be one of those things that we don't realy want to work to to its potential in real world conditions. The idea that there is a temperature at which the reaction will work best or at its highest potential does not necessarily mean that the clandestine cook, or his product, would be advised to crank the heat up to that temperature.

Then again I could be completely wrong. It would not be the first time, by any stretch of my imagination.


  • Guest
Good answer geez,
« Reply #5 on: December 31, 2003, 01:33:00 AM »
The reason i brought this up is that recently I have been getting not so good results and after many hours of checking this and that and for a while i blamed it on the homemade hypo.

During this testing time i was under the impression that i was keeping the temp of the rxn at around 120C.  However, i didn't measure the temp due to not having a thermometer due to similar episodes to geez and his thermometers.

I tried increasing the rxn times but always kept the hotplate on or below the number that i had previously measured as being 120C. 

Anyways after much hair pulling i finally remembered to pick up a new thermometer while at the chem supply.  What i found was that i had been cooking at about 100C all this time.  I just finished a 13g cook which i kept between 120C -130C for 12 hours and i am now feeling what i have been after for what seems like a lifetime.

After reading geez's reply, i now think that i when i make the hypo and evaporate the water off, a good portion of my hypo is oxidizing to phosphorous acid which is most likely the reason for needing higher temps than those geez used in his hypo rxns.  I also try to get my hypo to about 50% whereas geez would concentrate his to 85%+. 

Nevertheless, i finally found the answer to my problem and will make sure to have a working thermometer from now on.


  • Guest
Time and Temp
« Reply #6 on: December 31, 2003, 04:40:00 AM »
>I have not duplicated the experiments with temperature variations with the long wet reflux.

Ibee has!
Back before the LWR really took hold as a viable alternative to the more popular Hot/Fast P/P, Ibeeware did many tests in his quest for thesholds and absolutes.
It was easy to discern some of the differences in quality and the relationships associated to time/temp/hydration during bio-assay.
However, the lack of formal chemistry knowledge presented some pitfalls that demanded recreating unpleasant samples to arrive at consistant data and their possible causes.

We know that the aziderines(iodosides?) and impurities created during Hot/Fast rxn are many and from what I gather now, it's becoming more clear that most are likely created by that dissociation described above.
When one looks at the principal behind what's described as taking place, high temperature (120°C) to iodine and hydrogen, it conjurs UP some pretty vivid images and finally a smidgen of understanding.
At least for me.
Not having the mental aptitude to play out rxns in my mind, prevents me from further expounding on the intricacies in depth.
But We do know that HI recycles and I've seen diagrams of what is suppose to take place in the creation of hydriotic acid.
The above quoted statement is true but it would also be influenced by the Dissociation constant that would be effected by variables introduced.
Those variables seem to bee the topics of the most debate as of late regarding the two main factors, hydration and temperature. Well, three actually when time is factored in.
It's also a well known fact that higher temps applied to the rxn will bring it to completion sooner.
This fact supports the findings in the above quoted statement. But that statement by itself leaves out the important factors that influence the product produced and the amount of impurities imparted above that 120°C temp.
Therefore it still stands to reason that a controlled longer rxn utilizing a less harsh/reactive reducing agent (inder it's full potential) is gentler on the end result.
I still like Rhodiums analogy about the turkey in the oven at 500°F for an hour compared to the turkey in the oven for 3 hours at 350°F.
Which would you eat?
Not only that but lets go a step further because some think this way without considering the bigger picture(I know I did...)
As opposed to cooking the bird at that time/temp rule above, let's factor in the other variables:
Temp + Time per pound(rxn size)
Stuffed(gaaked) or UnStuffed(pristeenclean)
Okay...I'd apologize for rambling but the turkey needed to get all that off his chest ;D

Either I'm halucinating or Geez editted his reply since I read it first and started this one! ;)
Either way we both agree that the LWR produces superior end result!
How and why is left UP to the scientific minds to discern!


  • Guest
question for geez
« Reply #7 on: December 31, 2003, 05:54:00 AM »
hey, bud?

may i ask where you take the temp?
in the bath?
in the flask?
have you tested the thermometer against a known (i.e., boiling water)?

just curious about this strange data


  • Guest
« Reply #8 on: December 31, 2003, 09:51:00 AM »
Temps were in the flask. Thermometers were considered as accurate. (By golly, water boiled right at 100C on most all of them.)

I do not suggest that my measurements are perfect, nor my memory as good as I like to think, and admit that I break thermometers with the deft skill of the inherently clumsy.


  • Guest
SWIF can attest to this being true also.
« Reply #9 on: January 03, 2004, 10:10:00 AM »
SWIF can attest to this being true also.  When he was a newbee, he started a reaction and set it on too high, making it reflux  too quickly.  Long story short, there was a volcanic eruption of HI from the flask.  So the next time, he made it only slightly refluxing (~100C).  After 14h, no substantial product at ALL -- All he got was pseudo/ephedrine back.


  • Guest
all swibb can attest to is h3po3
« Reply #10 on: January 03, 2004, 11:20:00 AM »
swibb can cooberate geez's observations as well. in his experience an hp3o3 rxn is definately something that needs the higher heats. swibb has run the rxn as high as 130C or so for 3 hours in reflux with good yield results (though he did notice a twinge of the creepies) and conversly has run a similarly sized batch at 100C for 8 hours in reflux an came back with half assed dope. swibb DID however notice a pretty marked difference in quality when he drove the rxn to 130C then dropped the temp down to 100C for reflux, and also xerimened with bouncing the temp between 100C and 130C at regular (45min) intervals. both of those rxns had better results than the rxn where the temp was kept at 100C, but all three rxn's that involved reflux at 100C were of lower quality overall tha the rxn that sustained 130C.

as a side note the bouncing temp rxn was also used in an additional experiment for running a sealed rxn. this yielded even better results than all other rxns tested and in 2/3 the time, but sealed rxns gave swibb hell in he form of flying shards of pyrex so he has pretty much abandoned the sealed reaction route.

also, one thing that swibb forgot to mention, at the higher temp swibb started using boiling stones (swibb knows that other hav mentioned using peces of glass etc). at first swibb tried using a small glass marble as a boiling stone, ut the problem with that is that glass makes a horrible boiling stone. it is too smooth. the only reason that broken glass works at all is because of the rough broken edges. swib made his boiling stones from sall glass marbles that he then ground using a carbide tile cuttig tip and his trusty dremel. it is iimportant to grind all smooth area on the marble. now every rxn that swibb does he adds atleast 2 stones (no more tha 2 needed until you get in the 224g p/fed range). the use of these stones has increased the speed of swibb's rxn's dramatically and yield has even gone up slightly. for explanation of the reasoning is from the organic chem lab survival manual by james w. zubrick
A close up comparison between a boiling stone and the inner wals of a typical glass vessel reveals tousads of tiny nucleating points on the stone where vaporation can take place, in contrast to e smooth glass surface that can hide unsightly hot spots and lead to bumping, a massive instantaneous vaporation that will throw your product all over.


  • Guest
Super heating
« Reply #11 on: January 04, 2004, 02:47:00 AM »

When he was a newbee, he started a reaction and set it on too high, making it reflux  too quickly.  Long story short, there was a volcanic eruption of HI from the flask.

This is super heating. Use glass boiling chips to minimize super heating.


  • Guest
Juses chreest! Are we back on the 120c+ ...
« Reply #12 on: January 08, 2004, 06:55:00 PM »
Juses chreest!

Are we back on the 120c+ movement again???
Have thing come full circle or what??

WHy does HI need to disasicoiate at it natural disasociation temp for it to reduce iodoeph?
120c min?Are you sure?

Why not 80degC?
Why not Warm weather.Ask worlock If yer game.

Yeah 120 deg is where the two split if heated in a pot,
but what of the natural forces we encounter when ephedrine is introduced then halogenated?

Has anyone ever timed how long it takes for HI to halogenate?
How is hydrogen and iodine going to form the intermediate?
Im sure a little coaxing is required,but surely we dont need to slam them moles appart with such ferocity in order to accomplish a reduction.

If 120deg is the minimum,am swmIm ingesting something other than meth as a result of sub100deg cooks?
80-90degrres and TIME has always done it.Fuck the bubbles,
all they do is make me feel like a chemist anyway.

Who said we need a reflux?
Is it the temp of the HI, the H20 or the ephedrine which counts?
Back to reactions under vaccum then,that is if bubbling is all that matters,or if dissasociation is what makes our meth.
Suck that atmosphere out and let it boil at 20 degreez should do it.

We could hydrogenate using iodine as a catalyst perhaps and water as a solvent.

Are these truely the principles behind this rxn, or is this just more stabbing at shaddows?

Ahhhh to ponder on such whimsicle thoughts.

Rhod, It was your "excellent idea" that led swim to warm and not cook her rxns in the first place.
Explains them nasty sores and wind tunnel sinuses I spose.
I swear the pinweels swlI get from her warm cooks will rival the best of the best,even if they are kinda yellow.

Happy new year lovely bees.
Stay safe.


  • Guest
« Reply #13 on: January 09, 2004, 07:45:00 PM »
Rhod, It was your "excellent idea" that led swim to warm and not cook her rxns in the first place.

What are you talking about here? Haven't I always told you to reflux the reaction overnight using a lot of water?

I think you are confusing my statement "never run hot and dry" with the incorrect interpretation "don't heat to reflux".


  • Guest
50% hypo what is the rest does it contain,...
« Reply #14 on: January 10, 2004, 11:46:00 AM »
50% hypo what is the rest does it contain, water? from what ive read it does if this is correct then no addition of H2O is required it would only hinder the reaction dropping the HI concetration down to under %50 therefor halting the reaction. Rhodium told me not to add more H2O than you have Iodine does this mean to take into account the H20 already in the hypo. so a reaction that 100ml hypo 50%  0.965mol + min of 0.78mol of I2(= 197g 0.78*2 =1.56mol HI 199.5g enough to reduce 0.5mol of e .5*201= 100.5 g   with exces of .185mol H3PO2 = 12.2g+what ever water was left in the reaction

sorry if that doesnt make sense im tryin and ive been up for a few days
um what is the mol of H3PO3?


  • Guest
« Reply #15 on: January 10, 2004, 12:24:00 PM »
50% hypo what is the rest does it contain, water? from what ive read it does if this is correct then no addition of H2O is required it would only hinder the reaction dropping the HI concetration down to under %50 therefor halting the reaction.



  • Guest
Moles or Hamsters...take yer pick!
« Reply #16 on: January 10, 2004, 05:31:00 PM »
um what is the mol of H3PO3?

LoRE: See

Post 481689

(wareami: "Calculating moles software", Chemistry Discourse)

Peace of the reaction



  • Guest
ballzofsteel, You have "pinwheels"...
« Reply #17 on: January 10, 2004, 05:57:00 PM »
ballzofsteel, you have "pinwheels" after you finish your rxn's??? This confuses SWID, pinwheels ARE un-reduced psuedo and definitely NOT something you want in your final product, that is not unless you enjoy doing psuedo. The meth crystal is NOT a pinwheel, not even close.


  • Guest
Excellent ideas
« Reply #18 on: January 10, 2004, 06:02:00 PM »
Rhod, I suspect ballz is referring to the suggestion you made a while back in

Post 352969 (missing)

(Rhodium: "Hypophosphorous acid reduction with 100% yield?", Stimulants)

I too wondered whether the 120oC required for the dissociation of HI to H2 and I2 was significant. I had thought the dissociation was necessary in order to provide a 'hydride ion' to reduce the iodoephedrine to methamphetamine; the reason being for this was that otherwise the only 'H' source would be the protons in the acidic solution which, with no electrons, would not be nucleophilic and would surely be unable to displace the iodide ion.

But then there are trusted bees who perform this reduction well below the dissociation temperature of HI; geezemeister has attested to this above, and there are reports in the scientific literature where such reductions are performed well below this temperature too, sometimes as low as 60oC, for example in the article

Tetrahedron Letters 42 (2001) 831–833


Reduction of 4-methylbenzhydrol (representative reaction):

Iodine (1.00 g; 4.0 mmol), 4-methylbenzhydrol (0.79 g; 4.03 mmol), and acetic acid (25 mL) were stirred under nitrogen in a flask equipped with condenser. Hypophosphorous acid (50% aq.; 2 mL; 19.3mmol) was added and the mixture was heated to 60°C. The mixture was stirred for 24 h, diluted with water, and extracted with hexane. The hexane was dried over MgSO4 and removed under reduced pressure. Analysis by GC–MS showed only a single constituent, 4-methyldiphenylmethane, produced in 100% yield.

So where does this leave us? There is obviously still confusion: this thread's very existence and the views expressed within it are proof enough of that. Attempting to put things in perspective, however:

120oC is obviously not the minimum temperature for the reduction of compounds by HI. As HI doesn't dissociate below this temperature, the reasoning must be, as with most things in chemistry, that the mechanism isn't as clear cut as the simplistic representation we use to enable our understanding of it. It could be that a partial dissociation is able to occur, possibly only in the presence of a reducible substrate, at a significantly lower temperature. It could be that the proposed mechanism needs a little modification: the

Final Word on the HI/P reduction mechanism

( is probably the most up to date and definitive proposal we have, but there is always the possiblity it isn't entirely accurate or complete.

It could just be that I've missed the point entirely, but this is the best it's going to get for me tonight.

Any thoughts?


  • Guest
Direct reduction mechanistically possible?
« Reply #19 on: January 12, 2004, 02:27:00 PM »
Is it possible for hypophosphorous acid to reduce iodoephedrine directly at lower temps without going through HI?

If hypo can reduce iodine to HI and HI can reduce iodoephedrine to meth, it should at least be theoretically possible for hypo to do it too, provided that there is a mechanism for it. That I don't know, but it would explain some special circumstances surrounding the hypo procedures in particular (as opposed to HI/P).