The Hive > Stimulants

Iodination of benzylic alcohols w/o HI

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aYoungKing:

--- Quote from: fishinabottle on February 20, 2015, 09:30:08 AM ---Prejudice doesn't go away in ten years, actually it never will. Just because the HI reduction was and is widely used by "cooks" and that it is ancient doesn't make it unclean, low yielding or whatever.
For a matter of fact a correctly done HI reduction of ephedrine gives excellent yields which were only beaten by the Birch (done by chemists in the lab, never reached in the field) and quality (selectivity) is excellent too. I can assure that catalytic hydrogenation of an ephedrine ester or haloephedrine provides yields which are not nearly as good and impurityies which are not easily removed and suspected to have nasty sideeffects on consumption.

For "reaction mechanism" hey! Chemistry has no working theory and those "mechanisms" are pure wanking. I have seen so many completely contradictional interpretations of the same reaction that I can tell you nothing is so useless like this. As it does not provide reproduceability for something related. Not at all.

How are reactions and compounds put to the test nowadays? Big companies in pharma run some thousands of robots which run a 50 reactions a time and analyse the results all automated. Who would do this if he would know "reaction mechanisms"?  Industry uses another approach as stuff is usually simpler in structure and that is "we have to much of A and we want B , some hundred bar of pressure and some zeolithe will do" And thats it.

Chemistry has long since outlived itself for the idea at start was: If we do enough reactions and analyse the outcome we will soon be able to see a structure, develop a working theory and then we are able to synth everything we want, we are god then. Lets exchange our results and 20 years max and we have it.
And so they did.
It was about 1880.

Bad luck boys.


/ORG

--- End quote ---

now i'm starting to get a hint of meaning of the "chemical racism" you mentioned above. rhodium being one of the bees, not a proud HI cooker and you can tell from his posts. max yield w/w in an HI reaction will get 92 percent i think, no one ever gets there though. what is the max yield anyone has ever heard of from a chloroephedrine batch? actual yield as ephedrine converted to meth, and not measured by the yield of chloroephedrine to meth.

Impossible:

--- Quote from: fishinabottle on February 20, 2015, 09:30:08 AM ---Long post

--- End quote ---

Don't get me wrong, I agree with you.  The HI/Phos reaction was one of the first procedures I performed, and one of the ones I've studied the most.  If anything I'd prefer as much discussion on (any) reaction as possible.
--- Quote from: aYoungKing on February 20, 2015, 01:08:21 PM ---

now i'm starting to get a hint of meaning of the "chemical racism" you mentioned above. rhodium being one of the bees, not a proud HI cooker and you can tell from his posts. max yield w/w in an HI reaction will get 92 percent i think, no one ever gets there though. what is the max yield anyone has ever heard of from a chloroephedrine batch? actual yield as ephedrine converted to meth, and not measured by the yield of chloroephedrine to meth.

--- End quote ---

Highest yield reported in literature was around 90% using supported palladium or platinum catalysts.  The multitude of reported yields on the hive/wetdreams etc. can't really be considered reliable information for the most part, but the general consensus for HI yields was "decent."

Many people tried out the catalytic hydrogenation procedures with dissappointing results.  It turns out the catalyst preparation has a huge impact on it's performance and the reports were mostly self prepared.   

fishinabottle:
no no no....
It is 92g of meth from 100g of ephedrine is the most one could get as that would be 100% yield.
Not 92% thats wrong.

HI reduction proceeds best in batches between 100g and 500g ephedrine, more or less then this diminishes yields (not extremly but noticeable). From 1kg ephedrine 800g meth (both as HCl salt) can be expected, and 800g with 920g as 100% says 87% yield, up to 90% more has been reported but I doubt the validity of the claims as product was not recrystallized or even dried and crystal-water + HCl adds up to 10% weight or more what explains reports of 104g meth from 100g ephedrine.
The 87% are recrystallized shards bonedry.
One does not get this on the first shot, or with much luck only.

Don't want to comment on Rhodium except that he is completely overrated, when searching for information, valid information in the archives I go for other names first and read Rhodiums posts only for completeness. Be warned he and Barium loved to include "typos" on amounts or other things confusing into their posts, if taken verbatim and not recalculated you can get royally fucked.

The majority of bees were meth cooks, those into MDMA only represented only a marginal faction.

/ORG

Vesp:
Would be cool to create a new archive like rhodiums. Fix errors, etc.

aYoungKing:

--- Quote from: fishinabottle on February 27, 2015, 07:57:21 AM ---no no no....
It is 92g of meth from 100g of ephedrine is the most one could get as that would be 100% yield.
Not 92% thats wrong.

HI reduction proceeds best in batches between 100g and 500g ephedrine, more or less then this diminishes yields (not extremly but noticeable). From 1kg ephedrine 800g meth (both as HCl salt) can be expected, and 800g with 920g as 100% says 87% yield, up to 90% more has been reported but I doubt the validity of the claims as product was not recrystallized or even dried and crystal-water + HCl adds up to 10% weight or more what explains reports of 104g meth from 100g ephedrine.
The 87% are recrystallized shards bonedry.
One does not get this on the first shot, or with much luck only.

Don't want to comment on Rhodium except that he is completely overrated, when searching for information, valid information in the archives I go for other names first and read Rhodiums posts only for completeness. Be warned he and Barium loved to include "typos" on amounts or other things confusing into their posts, if taken verbatim and not recalculated you can get royally fucked.

The majority of bees were meth cooks, those into MDMA only represented only a marginal faction.

/ORG

--- End quote ---

of course, yield by mole will be different that yield by weight.

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