PALLADIUM PI-ALLYL CHEMISTRY OF NEW P,S BIDENTATE LIGANDS - SELECTIVE BUT VARIABLE DYNAMICS IN THE ISOMERIZATION OF THE ETA(3)-C3H5 AND ETA(3)-PHCHCHCHPH PI-ALLYL LIGANDS

A series of palladium(II) complexes based on new P,S bidentate ligands have been prepared. One of these, exo-8-((o-(diphenylphosphino)benzyl)thio (3), is chiral. PdCl2(3), [Pd-(eta(3)-C3H5)(3)](CF3SO3) (9), [Pd(eta(3)-PhCHCHCHPh)(3)](BF4) (10), and other' complexes of P,S ligands with cyclohexyl and ethyl substituents (in place of the exo-borneol fragment) have been prepared. The cationic complex [Pd(eta(3)-C3H5)(3)](+) exists as two isomers in solution and reveals selective allyl dynamics which are controlled by electronic effects. [Pd(eta(3)-PhCHCHCHPh)(3)](+) exists in four forms and also shows selective dynamics which are controlled by steric effects. The solid-state structure of [Pd(eta(3)-C3H5)(3)](CF3SO3) (9), has been determined by X-ray diffraction methods. Complex 10 was used as a catalyst for both the allylic alkylation and the allylic amination. Although the chemical yields are high, the reactions are very slow and the ee's poor.