Sciencemadness Discussion Board

reduction of phenylalanine

nightshade - 5-5-2008 at 11:42

Took 6 grams dl-phenylalalnine mixed with methyl alcohol then with diluted hcl.placed into divided cell passed 1.5 amps for 11 hours.Dried out acid solution now have I guess about 6 grams of yellow crystals still moist with a little acid. What are those crystals.Now a amino acid will form a ester with alcohol if added to a strong acid.

solo - 5-5-2008 at 11:55

Well it's not the euro amine and and most likely the phenylalanine menthyl ester...........solo

Filemon - 6-5-2008 at 06:38

The reduction of Kolbe doesn't work with phenylalanine. It should not have anything in alpha, if it is not the case the reaction it fails or the yield is very poor. Maybe reducing with acid formic making the pyrolysis of the calcic salt Ca (CO2H) (ph-alanine) in a solution of ethelen glycol with hydrazine (protective group and reducer). The pyrolysis of the phenylalanine works to temperatures more lower that other organic acids.


Ca (CO2H) (ph-alanine) = (130-140ÂșC) => phenyl-2-aminopropanal + CaCO3

phenyl-2-aminopropanal + hydrazine => phenyl-2-aminopropanhydrazone

After to complete the reducion of Wolff-Kisnner filtering the CaCO3 and adding NaOH to the solution. I don't know if the reaction works. Although in theory it seems yes.

[Edited on 6-5-2008 by Filemon]

not_important - 6-5-2008 at 07:21

What reduction were you hoping for?

Organic electrochemical reactions often are sensitive to the electrode materials, pH, current density, temperature, and concentrations; none of which you listed. The same starting material can give several different products by varying those conditions.

What is a "reduction of Kolbe"? The Kolbe reaction/electrolysis is a oxidative dimerization, not a reduction; it is usually done in slightly alkaline solutions. But it is correct that it generally fails with electron releasing substitutes on the alpha carbon.

nightshade - 6-5-2008 at 09:14

carbon anode carbon cathod 9.5 volts 1.5 amps phenylalanine alcohol mix kind jelled up then mixed with the hcl,formed a crust during reduction broken up mixed back into solution a few times. Acid solution dried on hot plate forming light yellow crystals.Put clump of crystals on foil heated leaving some carbon on foil.What is the desired end product what would you get if added 6 electrons to phenylalanine and made into hcl salt.

nightshade - 6-5-2008 at 09:19

Chem guy had web site on it was some sort electrochemical reduction of phenylalalnine to amphetamine.It say like guy above some sort of kolbe reaction if I remember right.
What I really would like is one of you to run it and let me know what you what you think.When heated it smells right clean .

stoichiometric_steve - 6-5-2008 at 09:55

isnt this going in the wrong way?

shady guy turns up, asks n00b question, obviously related to drug manufacture, wants members to do the dirty work...

Polverone - 6-5-2008 at 10:10

He's been registered for a while. But, yes, it seems to be directed at drug production with little effort/curiosity... Nightshade, visit wetdreams and search for some of the phenylalanine electroreduction discussions. IIRC Uncle Fester tried it and thought that his reaction product smelled right but was unable to isolate anything.