[Urbanium]

Is anyone familiar with a solvent that might strongly suppress ionic polymerization?

I have one reaction in which unwanted ionic polymerization is largely responsible for depletion of the starting material, and the wanted reaction works only in presence of a metal triflate catalyst. Unfortunately the substrate, which is a ring, undergoes ring-opening and cationic polymerization in the presence of triflate and everything goes wasted. The approaches I was thinking about to fix that are:

a) take a similar metal catalyst with a counterion different than triflate (tried, that didn't work)

b) take a solvent which might strongly suppress cationic polymerization somehow (but I don't know any, checked Odian and there is nothing about that)

c) make the triflate anion solvated and "excluded" to some extent in some non-polar solvent (in a same way in which e.g. some potassium salts get dissolved in presence of 18-crown-6).

Does anyone know something analogous to crown ethers but for anions, either triflate or in general?

[Urbanium]

Anyone?

[wildfyr]

Oxygen, carbon dioxide, and protic stuff kills anionic polymerization

[C-hemCards]

I'm not sure what your exact reaction is, but sometimes the mode of addition (catalyst to substrate or substrate to catalyst) can slow or eliminate polymerization. Same goes for addition rate.

In the end, it's very likely going to depend on your (desired) reaction rate.