Author Topic: basifying with NaOH instead of KOH  (Read 1783 times)

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edo

  • Guest
basifying with NaOH instead of KOH
« on: April 16, 2004, 05:30:00 AM »
Swim is doing Osmium/BrightStar Reductive Amination (

https://www.thevespiary.org/rhodium/Rhodium/chemistry/redamin.os-bs.html

).

 Swim wants to substitute 230g KOH with NaOH.

 How much(grams) of NaOH does swim need to use?

Post 234266 (missing)

(grayIC: "NaOH versus KOH and others newbie questions.", Newbee Forum)

THanks.   :)

ApprenticeCook

  • Guest
use the mol.w and work it out...
« Reply #1 on: April 16, 2004, 09:07:00 AM »
use the mol.w and work it out... if you dont know how its a bit strange your doing any chem proceedures at all.

Here it is...
mw(KOH) = 39.1+1.008+16 = 56.108
mol(KOH) = 230/56.108 = 4.099
mw(NaOH) = 22.99+1.008+16 = 39.998
mass(NaOH) = 4.099*39.998 = 163.95g

You need 163.95g of NaOH. Good luck.
-AC

edo

  • Guest
Thanks for calculations. :-)
« Reply #2 on: April 16, 2004, 11:19:00 AM »
Thanks for calculations.



:)

edo

  • Guest
concentration of acid
« Reply #3 on: April 17, 2004, 02:20:00 AM »
Swim just bought sulfuric acid from local auto store. After looking at the MSDS sheet it only contains 10% H2SO4

http://www.jtbaker.com/msds/englishhtml/s8236.htm



In LoBtops write up

Post 208821 (missing)

(LaBTop: "The ONE and ONLY buffered Performic", Methods Discourse)
he uses 15%  H2SO4.

Is 10% ok?

Thanks

Rhodium

  • Guest
should work
« Reply #4 on: April 17, 2004, 02:23:00 AM »
It should work, just let it react for a little longer, say 3.5 hrs.


ephemeral

  • Guest
H2SO4 vs. HCL for glycol hydrolysis
« Reply #5 on: April 17, 2004, 03:04:00 AM »
referencing  Chromics HCL post  (476334) and V. Verdsegast there as well concerning HCL in place of sulfuric,  they used an alcohol solvent with the glycol, then H2O with the HCL.
      The question is, what ratio of  alcohol/water/acid is appropritate? That is, how is the amount of solvent determined in each case, a molar ratio?  But when scaling up, is it correct to increse the solvent quantity accordingly, or use a lessor amount?
  Thanks for any reference

edo

  • Guest
Thanks Chief Bee! :-) For some reason swim...
« Reply #6 on: April 17, 2004, 04:10:00 AM »
Thanks Chief Bee! :)

For some reason swim thought H2O2 otc was 35%(but it only 3%).  Swim mixed the 3% H2O2 with formic acid and dripped 1/2 of solution into iso,baking soda,dcm before he realized his mistake.  Yea swim is an idiot  :o

What should swim do?
Swim will be picking up 35% H2O2 soon from local chem shop.
for now can swim take 3% H2O2 and boil off water to concentrate the H2O2 until 35% is achieved
Can iso,Na2CO3,dcm mixture be saved?

Plz advise
xia xia :)

ephemeral

  • Guest
Sorry to be repetative, but could someone give
« Reply #7 on: April 27, 2004, 04:14:00 AM »
Sorry to be repetative, but could someone give advice on the proper ratio of  HCL/alcohol/glycol  when unsing HCL for a glycol hydrolysis  in a performic rxn?

   TFSE is still closed and cant find this info.  Also, is standard  muriatic equivlent to 5 normal? ie  15%  ?

 thanks much :)

amine

  • Guest
The ratio....
« Reply #8 on: April 27, 2004, 04:48:00 AM »
2g glycol : 3ml MeOH : 5ml dH2o : 5ml 31.25% HCL

so a nice 2:3:5:5 ratio :).

Reflux for 2.5hr.

The temp of the solution should stay around 86C during the reflux.

Scale up as your see fit. (Swim did a nice scale up on 200g of glycol..all went well) (this are Chromic's specs adjusted  a little bit)

ephemeral

  • Guest
My sincere thanks Amine!
« Reply #9 on: April 29, 2004, 04:35:00 AM »
My sincere thanks Amine! :)   Coulnd't seem to properly extrapolate this info, and this was likely one of the errors in SWIMs earlier runs.  Will apply and report results.