Sciencemadness Discussion Board

Phenylacetylcarbinol. - how's it made?

Yttrium2 - 24-2-2019 at 03:35

So I go to Wikipedia to see how pseudoephedrine is made, it says it's made by l pac. But how is l pac made?

I read yeast ferments dextrose in presence of pyruvate decarboxylase enzyme and then benzaldehyde is added.


Why do I feel like something is left out?


I don't understand the chemistry behind this.


It doesn't seem as clear cut as other chemical reactions, from what I understand, and I know little about chemistry but I can generally follow the pathways off by anecdote and come to some sort of conclusion about whether or not the schema will work.

Can someone go into a bit of detail about what is pyruvate decarboxylase, dextrose, benzaldehyde, how long have these chemicals been in use, and how long has this fermentation technology has been around? I.e. how'd they figure it out?

A bit of a general debriefing would be nice. -- with the neat area 51 esque pictures of the early yeast reactors ECT...



Also, if anything else, can someone explain this
It says it's produced in countries "
where economic and industrial conditions favor its mass production for export.[8]"




[Edited on 2/24/2019 by Yttrium2]

j_sum1 - 24-2-2019 at 03:41

How is this not a spoonfeeding request for ephedrine precursors?

This better be good or I am sending it to Detritus.

Metacelsus - 24-2-2019 at 05:04

I don't think this is necessarily spoonfeeding; Yttrium2 is just asking a biochemistry question.

Basically, pyruvate decarboxylase normally converts pyruvate into acetaldehyde + CO2 using a thiamine cofactor. However, in the presence of benzaldehyde, the thiamine-bound intermediate can react with benzaldehyde to form L-PAC instead of releasing acetaldehyde.

edit: see this paper for more details

[Edited on 2019-2-24 by Metacelsus]

Attachment: 1-s2.0-S0922338X97819009-main.pdf (750kB)
This file has been downloaded 415 times

Tsjerk - 24-2-2019 at 07:49

Quote: Originally posted by Metacelsus  

Basically, pyruvate decarboxylase normally converts pyruvate into acetaldehyde + CO2 using a thiamine cofactor. However, in the presence of benzaldehyde, the thiamine-bound intermediate can react with benzaldehyde to form L-PAC instead of releasing acetaldehyde.


As chemical synthesis of this two stereo-isomer center containing molecule probably is not economic.

[Edited on 24-2-2019 by Tsjerk]

Waffles SS - 24-2-2019 at 08:18

All possible way for synthesis (RS)Phenylacetylcarbinol

Attachment: PAC.pdf (364kB)
This file has been downloaded 871 times

Corrosive Joeseph - 24-2-2019 at 09:16

Quote: Originally posted by Waffles SS  
All possible way for synthesis (RS)Phenylacetylcarbinol


Thank you for that........... But the racemate is not a desirable end product, because it kinda defeats the whole idea of this route.


/CJ

Waffles SS - 24-2-2019 at 09:24

Quote: Originally posted by Corrosive Joeseph  
Quote: Originally posted by Waffles SS  
All possible way for synthesis (RS)Phenylacetylcarbinol


Thank you for that........... But the racemate is not a desirable end product, because it kinda defeats the whole idea of this route.


/CJ



Attachment: L-PAC.pdf (404kB)
This file has been downloaded 464 times

[Edited on 24-2-2019 by Waffles SS]