The Hive > Stimulants

Iodination of benzylic alcohols w/o HI

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aYoungKing:
worth checking into, so bump.

fishinabottle:

--- Quote ---Most of these reduction methods are much milder and faster than HI reflux, allowing for higher yields and most definitely a purer product.

--- End quote ---
This is complete bullshit. Every single point of the sentence. Astonishing ignorance and it speaks for a kind of "chemical racism".


oh my
/ORG

aYoungKing:

--- Quote from: fishinabottle on February 19, 2015, 10:59:27 PM ---
--- Quote ---Most of these reduction methods are much milder and faster than HI reflux, allowing for higher yields and most definitely a purer product.

--- End quote ---
This is complete bullshit. Every single point of the sentence. Astonishing ignorance and it speaks for a kind of "chemical racism".


oh my
/ORG

--- End quote ---

lets not forget that this the post was written in 2004.

Impossible:

--- Quote from: aYoungKing on February 20, 2015, 03:20:21 AM ---
--- Quote from: fishinabottle on February 19, 2015, 10:59:27 PM ---
--- Quote ---Most of these reduction methods are much milder and faster than HI reflux, allowing for higher yields and most definitely a purer product.

--- End quote ---
This is complete bullshit. Every single point of the sentence. Astonishing ignorance and it speaks for a kind of "chemical racism".


oh my
/ORG

--- End quote ---

lets not forget that this the post was written in 2004.

--- End quote ---

That's not quite as relevant as you might think.  The HI/(P4/H3PO2/H3PO3) is one of the most discussed, and most poorly understood reactions on drug chemistry boards.  Although the exact mechanism  isstill not completely agreed upon by professional researchers  and nothing new has really come of it in the last 10 years to be fair. 

fishinabottle:
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

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