Main Index   Search   Register   Login   Who's Online   FAQ   Links
  2 Online, 0 Active   You are not logged in  
Main Index     The HIVE light edition (TM)
This is a historical archive
The forum is read-only. Private information has been removed. It is not possible to login.


Newbee Forum  

All 4 posts   Subject: Urushibara Confusion   Please login to post   Down

 
    Drug_Phreak
(Hive Bee)
11-06-04 02:31
No 539954
      Urushibara Confusion     

SWIDP is about to dream up some TMA-2, but is slightly confused about the production of urushibara catalyst in Atibody2’s write-up. In Atibody2’s write-up it says:


Catalyst prep

"To a solution of 1ml 31% HCl, 40g NiCl2.6(H20) in 350ml EtOH in a 500ml beaker at 50°C is added 35g of shredded Al (regular Reynolds foil) slowly over a 3.5 hour period, when evolution of hydrogen had ceased the rxn was a viscous gel. This was placed in a 4l beaker and rinsed several times with tap water, each time allowing suspension to settle before decanting. This precipitated nickel was air dried overnight on a filter paper (Note: larger pieces of foil were removed)."

Then it says:

Activation

"10g of the above catalyst was placed in a beaker containing 385 ml 40% aqueous AcOH and 89g NaCl at 70°C for 7 minutes, then the solution is decanted and the Nickel rinsed with 60°C dH2O, then rinsed with EtOH then placed in a 500ml Erlenmeyer flask containing 250ml EtOH and charged with 20mmol TMP2NP (5g). With moderate overhead stirring, 10g of Al is added 1g at a time followed by a 3ml aliquot of 31% HCl with each addition."



The way this is written it seems like it is saying to use the dried nickel from the Catalyst prep in the activation step. Is this the case? I thought this type of urushibara was basically made like Al/Hg. Shouldn’t the Aluminum foil from the Catalyst prep step be used instead of the precipitated nickel? Also, can’t the toluene just be gassed after the EtOH is stripped off instead of adding pre-gassed toluene?

Crank is part of this complete breakfast.
 
 
 
 
    Rhodium
(Chief Bee)
11-06-04 08:50
No 540006
User Picture 
      Urushibara-Ni reduction basics     

The way this is written it seems like it is saying to use the dried nickel from the Catalyst prep in the activation step.

Yes.

Is this the case?

Yes.

I thought this type of urushibara was basically made like Al/Hg.

No.

Shouldn’t the Aluminum foil from the Catalyst prep step be used instead of the precipitated nickel?

No.

Formation of Urushibara-Nickel from aqueous NickelII ions and aluminum foil:
3 Ni2+(aq) + 2 Al(foil)   3 Ni(powder) + 2 Al3+(aq)

Read up on more Urushibara-Ni reduction theory here (and UTFSE as well):

https://www.rhodium.ws/chemistry/amph.urushibara.html
https://www.rhodium.ws/chemistry/urushibara.html

The Hive - Clandestine Chemists Without Borders
 
 
 
 
    Drug_Phreak
(Hive Bee)
11-06-04 18:30
No 540046
      Thanks!     

I read the second document you posted, but I somehow skipped over the one by Ritter, which was really informative. Ritter says that after toluene extraction a bee can just work up in the normal manner. I guess this applies to TMP2NP too and it can just be gassed also huh? Also, Antibody2 says: Rxn is then slowly basified with 50% NaOH, but it doesn't say how much NaOH solution to use. Would 100ml be sufficient?

Crank is part of this complete breakfast.
 
 
 
 
    Rhodium
(Chief Bee)
11-07-04 17:19
No 540218
User Picture 
      basification     

You are supposed to use pH paper to determine how much NaOH you need to add to basify (to pH 10-11) - it varies from case to case.

The Hive - Clandestine Chemists Without Borders
 
 

All 4 posts   End of thread   Top
   

 https://the-hive.archive.erowid.org    the-hive@erowid.org
   
Powered by KleenX(TM) v.5.06, Copyright 2020 - 2021, MDMA-Soft Computer Services

Links     Erowid     Rhodium

PIHKAL     TIHKAL     Total Synthesis II

Date: 05-19-24, Release: 1.6 (10-04-15), Links: static, unique