p2np->amphetamin with urushibara-dont work!!

Vitus · Psychoscientist

Long time ago I also tried it on 2,4,5-trimethoxyphenyl-2-nitropropene using Urushibara nickel prepared from kitchen Al foil, following Ritter's procedure, I remember that it was very messy and my yield of product was very low.

An idea that popped in my mind back then was to use an ultrasonic bath when preparing the catalyst, hoping that the larger surface area of the Ni deposited this way would increase its catalytic activity, but the idea was never pursued.

jory · Mon Apr 25, 2005 11:34 pm

maybe better idea is reduce p2np to p2p using Fe/HCl and reductive amination (or other method).

IndoleAmine · Dreamreader Deluxe

But then its no phenyl-2-nitropropene reduction anymore, and thus none of those handy-dandy 2-step routes from aldehydes to amines... Wink

brain · Linguist Extraordinaire

no ! i try this method,,, i hate it Smile

... its so messy, and low yeld,, that i trow this method from my head Smile

... better al/hg Smile

IndoleAmine · Dreamreader Deluxe

Have you already tried making p2p oxime and reduce it with elemental sodium/anhydr.EtOH? 90% conversion. Wink

joe_aldehyde · huxleys associate

i tried the procedure according to ritter last night, the strange thing about the preparation was that i dissolved exactly 4.000g in 75ml of ethanol, heated to 50deg.c, started adding Al-foil (consumer grade thin shit) and way before all 5g Al foil were added, no more hydrogen evolution occured. now i have a big suspension of Al foil nuggets, Ni powder (doesn't settle to bottom, even on dilution) and don't know what to do with it since "washing" isn't going to work unless i filter the Ni powder off (and THAT is seriously going to clog up my filter paper - any hints? got no celite, too sad).
should i also keep the leftover Al foil from the suspension? i don't know if conversion of Ni(2+) to Ni(0) is complete since i can't see the colour of the solution (the precipitated nickel is a very dark grey, at least that seems to have worked out as desired).

Senfgas · Mon May 30, 2005 7:48 pm

The procedure demands for adding HCl along with the foil, until it is dissolved....

joe_aldehyde · huxleys associate

it demands for adding 1ml of HCl to initiate the reaction (did just that, actually more like 2ml), but not until the addition of the substrate is added more HCl. i know the writeup by heart Smile

should i just keep adding HCl?

Senfgas · Mon May 30, 2005 7:55 pm

If you need it I will repat myself:

The procedure demands for adding HCl along with the foil, until it is dissolved....

joe_aldehyde · huxleys associate

don't be a jerk please,

here is the original text:

Dissolve 4.0g Nickel Chloride hydrate (light green crystals) in 75 ml 95% ethanol w/ mag stirring and warming to 50°C. After salt is dissolved remove stir bar and add 1ml water and 1ml conc. HCl. [1] While solution at 50°C slowly add 5g regular Reynolds wrap torn up into 0.25 x 1.0in strips in 1g portions with manual stirring. The aluminum will SLOWLY react with the nickel salt forming the metal Ni(s) through metathesis as a dark grey chunky powder which settles to the bottom. A gentle effervescence of hydrogen occurs during reaction. Add aluminum at a rate that maintains a steady effervescence and keeps temperature roughly in the 50°C range. Note this may take up to two hours! At the end of Al addition all green color from nickel salt should be discharged. If any color remains add another gram of aluminum and wait for soln to clear. Precipitated Nickel powder was added to 100ml 20% NaOH soln and manually stirred at 60°C for 30 min. Excess NaOH is decanted and nickel is washed with 5 x100ml aliquots of distilled water to remove excess base. At this point Urishubara nickel catalyst is prepared and ready for reduction.

so, i may be blind, but until the catalyst is ready, no more addition of HCl is noted.

Senfgas · Mon May 30, 2005 8:04 pm

Sorry I had thought you talk about the reaction not catatyst preparation. oops..