PREPARATION AND REACTIVITY OF 1,2-BIS(IMINO)ETHYLPALLADIUM(II) COMPLEXES

Article abstract of DOI:10.1016/S0022-328X(00)85578-3

The 1,2-bis(imino)ethylpalladium complex, (R=p-C6H4OMe, DAB^I) can be prepared by treatment of with two equivalents of CNC6H4OMe-p followed by slow addition of HCl at -70 deg C.The ?-bonded 1,2-bis(imino) group can be easily monoprotonated and undergoes acid hydrolysis to give the α-aldehydoimidoyl derivative .Condensation of the aldehydic carbonyl group with methylamine yields the product , DAB^II, with different substituents on the N-imino atoms.Substitution of ancillary ligands at the palladium center of DAB^I by dimethyldithiocarbamate anion (dmtc) affords the complex , DAB^III.The DAB^I, DAB^II and DAB^III derivatives react with anhydrous metal chlorides, MCl2 (M=Co, Ni, Cu, Zn) to give 1/1 adducts in which the 1,2-bis-(imino)ethyl group acts as a chelating bidentate ligand.Magnetic moment measurements and the far-infrared and electronic spectra of these binuclear compounds indicate an essentially pseudo-tetrahedral configuration at M.The reaction of DAB^I with 3-2-MeC3H4)>2, or 4, (DAB^I/Pd or Pt ratio, 1/2) involves the exchange of Cl^- and PPh3 ligands, which leads to the formation of the zwitterionic binuclear derivatives 3-2-MeC3H4)(DAB^IV)>, or 3-C3H5)(DAB^IV)> , and 3-2-MeC3H4)(PPh3)>, or 3-C3H5)(PPh3)>.