Di‐n‐alkyl‐(N‐ligand)palladium(II) complexes. Thermolysis and reactions with olefins

Abstract

Abstract(2,2′‐Bipyridine)diethylpalladium(II) reacts with electron‐deficient olefins (methyl acrylate, acrylonitrile, dimethyl fumarate, dimethyl maleate, maleic anhydride, fumaronitrile and tetracyano‐ethylene) to produce, with the exception of acrylonitrile, almost exclusively n‐butane as the product of reductive elimination. Apart from methyl acrylate and acrylonitrile, organometallic reaction products, (2,2′‐bipyridine)olefinpalladium(0) complexes, are isolated. The temperature dependence of the 1H NMR and 13C NMR spectra of the fumaronitrile complex demonstrates reversible dissociation of the olefin. The thermolysis of the diethylpalladium complexes with 4,4′‐dimethyl‐2,2′‐bipyridine or o‐phenanthroline as ligands leads to no change in behaviour. (2,2′‐Bipyridine)di‐n‐propylpalladium shows, upon thermolysis, the same product distribution as does the diethyl complex, i.e. propane/propene in the absence of olefin and n‐hexane in the presence of tetracyanoethylene.