X-ray structural and dynamic behaviour study of allyl palladium compounds with fluorinated benzenethiolate bridges

In solution, allyl palladium homobimetallic complexes bridged by fluorinated benzenethiolates, [{Pd(μ-SR)(η3-C3H5)}2] where R=C6F5, 1; C6HF4-4, 2; C6H4F-2, 3; C6H4F-3, 4 and C6H4F-4, 5, are found as a mixture of syn/anti and cis/trans isomers. The variable temperature 1H and 19F NMR study of these compounds show that the four isomers undergo interconversion through two probable mechanisms, allyl rotation assisted by the solvent and inversion of the configuration at the sulphur atoms. The X-ray crystal structure determination of [{Pd(μ-SC6F5)(η3-C3H5)}2] and [{Pd(μ-S C6HF4-4)(η3-C3H5)}2] shown both complexes to be bimetallic with the metal centres found in a slightly distorted square planar environments.