Print Page - basifying with NaOH instead of KOH

Title: basifying with NaOH instead of KOH
Post by: edo 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 (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. :)

Title: use the mol.w and work it out...
Post by: ApprenticeCook 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

Title: Thanks for calculations. :-)
Post by: edo on April 16, 2004, 11:19:00 AM

Thanks for calculations.

:)

Title: concentration of acid
Post by: edo 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 (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

Title: should work
Post by: Rhodium on April 17, 2004, 02:23:00 AM

It should work, just let it react for a little longer, say 3.5 hrs.

Title: H2SO4 vs. HCL for glycol hydrolysis
Post by: ephemeral 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

Title: Thanks Chief Bee! :-) For some reason swim...
Post by: edo 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 :)

Title: Sorry to be repetative, but could someone give
Post by: ephemeral 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 :)

Title: The ratio....
Post by: amine 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)

Title: My sincere thanks Amine!
Post by: ephemeral 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.

The Vespiary

The Hive => Newbee Forum => Topic started by: edo on April 16, 2004, 05:30:00 AM