Sciencemadness Discussion Board

mandelic acid - PPA/ephedrin ?

dextro88 - 20-10-2018 at 09:31

So, i was thinking obtaining some pac, from mandelic acid and lead acetate destructive destilation, but cant find much references abaut it, and will this PAC when reductive aminated give PPA or if methylated - ephedrine ?

And if i want to prepare a 3,4methylendioxymandelic acid with 1,3benzodioxole and glyoxylic acid can i just buble hcl gas thour them or what acid i need as catalyst.

[Edited on 20-10-2018 by dextro88]

JJay - 20-10-2018 at 09:41

Quote: Originally posted by dextro88  
So, i was thinking obtaining some pac, from mandelic acid and lead acetate destructive destilation, but cant find much references abaut it, and will this PAC when reductive aminated give PPA or if methylated - ephedrine ?


I don't think that will work. Just a word of advice: Do not refer to any substance as "pseudo," or people will mistake you for a drug cook and close your posts.

Quote:

And if i want to prepare a 3,4methylendioxymandelic acid with 1,3benzodioxole and glyoxylic acid can i just buble hcl gas thour them or what acid i need as catalyst.


There's a paper on vanillin on this site that discusses that reaction in a side note... I don't remember the details, but that part looked easy. I'm a little too preoccupied to hunt it down at the moment, but it is posted on the dopamine thread IIRC. Preparing protocatechualdehyde from the product is not easy, but I think boron tribromide works.

dextro88 - 20-10-2018 at 10:16

my goal here is to make nitration of 3,4methylendioxymandelic acid to piperonal as i need it for flowering properties, no protocatechualdehyde. but why you think the destructive destilation of mandelic acid with lead acetate will not work ? As i know this reaction is well known to clandestine chemists but with other target compund. I will try it i have some grams mandelic acid araund.

JJay - 20-10-2018 at 10:41

Alpha hydroxy acids tend to oxidatively decarboxylate at fairly low temperatures. I'm not 100% sure what would happen if you ran the reaction without oxygen, but I suspect it wouldn't go as you expect.

dextro88 - 20-10-2018 at 11:00

the reaction temperature is araund melting points of two, so i sugest no more than 150C, and just letting it destiling slowly,i pray it will not decarboxylate at this temperature, but if it what abaut doing the reaction in vacum and a little GAA as a solvent since at low temperature they will dont melt together, and reaction byproduct is gaa acid, so woud it hurt anythink ?

JJay - 20-10-2018 at 11:05

There might be some carbon monoxide produced. You should do this outside or in a fume hood. Also, please dispose of lead waste properly, and do not eat lead acetate, no matter how curious you are about its sugary taste. Wear gloves, etc.

With three oxygens bonded to two carbons, the electrons won't be spending a lot of time on the carbons, so they are susceptible to oxidative attack. I believe mandelic acid decarboxylates at around 150 C in the presence of oxygen. Without oxygen... my guess is that the carbonyl oxygen will try to bond with the alpha carbon. There are many possibilities after that.



[Edited on 20-10-2018 by JJay]

dextro88 - 20-10-2018 at 12:00

yea for shure i will make the reaction at vacum, and reaction will procced at araund 80-100C, so tomorow i am gone try it and we will see what will happen, anyone know melting point of PAC ? .

GrayGhost- - 20-10-2018 at 13:16

Quote: Originally posted by dextro88  
yea for shure i will make the reaction at vacum, and reaction will procced at araund 80-100C, so tomorow i am gone try it and we will see what will happen, anyone know melting point of PAC ? .


According to Wikipedia 39.47 °C (103.05 °F; 312.62 K).