Question

Because alcohol protons are reasonably acidic and easily undergo exchange, it is important that the base be matched to the appropriate solvent. Explain why it would be virtually impossible to sort out the factors, size of base or stability of alkenes formed, if a reaction were carried out using methanol as the solvent and potassium tert-butoxide as the base

Answer 1

If the elimination reaction is carried out in Methanol with tert. Butoxide as a base, the reaction would result in same outcomes even we reverse the order such as tert. Butanol as a solvent and methoxid as a base.

pKa of tert. Butanol is 18 and that of Methanol is 16. Hence this small difference in pKa will make the reaction of these two first go to the equilibrium. And then the resulting mixture of bases will give the elimination. This results in mixture of products such as less substituted alkene and more substituted alkene. Thus it will be difficult to determine effects of these bases on the outcomes of elimination reaction.