Equilibria involving allylbenzene, chloride ion, and palladium(II) in acetic acid solution

Abstract

The addition of allylbenzene to sodium di-μ-chloro-tetrachlorodipalladate(11) in acetic acid solution produces changes in the absorption spectrum which are compared with those produced by chloride ion and by pyridine. The occurrence and disappearance of certain isosbestic points over various ranges of ligand to palladium ratios together with evidence from plots of absorbance against mole ratio indicates that complex formation occurs in discrete steps. Evidence is presented which supports the view that under the conditions normally employed for the homogeneous catalytic isomerization of alkenes, the palladium is present as a monomeric palladium-alkene complex.