[organosurf]

Hi All,

I have this theory, not sure if its correct; please go thru' it and see if its correct or viable ?   
Normally made by : tBuOH + K → tBuO−K+ + 1/2 H2. (  It is a stronger base than sodium ethoxide. )
Where Potassium metal cannot be readily got or dangers of handling, transport, cost factors, etc limit this.
Is it possible to synthesize Pot-tert butoxide directly from TBA ( Tertiary Butyl Alcohol / iso-butyl alcohol / tertiary butanol  / iso-butanol ) which is obtained  from the dilute  mineral acid hydrolysis of MTBE ?
TBA has three “electron donating” groups, CH3- and  hence probably reacts faster with KOH.
In this case water will be given out which can be adsorbed by molecular sieves, or preferably absorbed by CaO ( which is cheap, easily available,dispensable ). 1g CaO absorbs 0.32g H2O. 
Molecular sieves have to be regenerated in vacuo, may be affected by K+
Dean-Stark trap can also be used, but adds to equipment set up. Use of azeotrope mixtures to be avoided, Benzene ( carcinogen ) + H2O BP=68  °C. Only Flask & reflux condenser setup preferred.
Can TBA be purified by freezing ? ( MP 25°C ). Reaction reflux temp about 90 °C ? BP of TBA is 85 °C.
Mechanical stirring preferred when using CaO. Reaction time probably 2 hrs ?
An excess of TBA can be added to dissolve the Pot. tert-butoxide, overcome CaO sludge, apart from that needed to react.  TBA does not react with CaO. Pot. tert-butoxide dissolves in the excess TBA, is simply filtered or decanted and the TBA evaporated to obtain the solid Pot. tert-butoxide.
TBA + Pot. tert-butoxide mixture itself can also be used in many instances.
                                                               
TBA  +  KOH (s) + CaO (s)    Pot. tert-butoxide ( t-BuOK )  +   Ca(OH)2
                                                                                           ( shifts equilibrium to the right )


Stoichiometrically :      (CH3)3COH  +  KOH  +  CaO     (CH3)3CO-K+   +   Ca(OH)2
                                      74g         56g       56g             112g                  74g

Total solids : 112g + 74g = 186g    Add extra 300ml of TBA  for the above molar ratios   

Quotes from literature :
“ when tert-butanol is deprotonated with a strong base, the product is an alkoxide anion.
   In this case tert-butoxide.”
“The tert-butyl alcohol is refluxed over quicklime CaO, distilled”
“ By adding electron donating groups to an alcohol, like -CH3, you are adding negative charge to the oxygen, which increases basicity and decreases the acidity and with that the hydrogen atom is off, the oxygen is less stable and more reactive wanting to attach to a positive charge somewhere ( K+  ? ).
If a hydrogen atom is lost from an alcohol, this gives rise to a neutral oxygen radical. This is not stable, and oxygen radicals are stabilized by the opposite things that stabilize an oxyanion (negatively charged oxygen). “
References that may help :
1 ) Patent for  aq KOH + TBA  http://www.freepatentsonline.com/4577045.html 
2 ) Patent for Sodium Methoxide USP 2,877,274
     [ Both the above are continuous process, not so user friendly, quite elaborate equipment setup. ]
3 ) British Patent 698,282 for Sodium Methoxide uses solid NaOH

Those well versed theoretically with the above and having the necessary apparatus can kindly carry out the above reactions to shed more light on this and share their findings with us.
Thanks in advance.

[discodermolide]

Sorry don't have a lab. and if I did I certainly would not have time to, nor be allowed to carry out experiments for third parties.