Abstract: | A kinetic study in tetrahydrofuran of the addition of 1,1-diphenylethylene on para-substituted styrylcarbanions (with Cs+ as counterion) has given the reactivities of free ions and ion-pairs. For both species, the addition rate constant increased in the following sequence for the substituent of the phenyl ring: pH < p-CH3 3O. It was also shown that in the same solvent, the dissociation constants of the polystyryl ion-pairs decreased with the electron-donating power of the substituent. |