PALLADIUM(II) HALIDE-COMPLEXES WITH DITHIOESTERS DERIVED FROM SARCOSINE

The compounds EtO2CCH2(Me)NCS2R (R = Me, ESDTM; R = Et, ESDTE) were pr epared from sarcosine ethyl ester hydrochloride, CS2 and alkyl iodide in EtOH-H2O. These ligands react with palladium halides in benzene to yield the benzene solvates [Pd(ESDTR)X2].nC6H6 (R = Me or Et; X = Cl o r Br; n < 1), in which the dithioester molecule coordinates through bo th sulphur atoms. Ligands and complexes have been characterized by i.r . and H-1 n.m.r. spectroscopy and by thermal analysis (t.g., d.t.g. an d d.t.a.). The low stability of the adducts in both solution and solid phase, is discussed on the basis of proton n.m.r. spectra. Thermal de gradation of the 1:1 complexes has been examined up to 1000-degrees-C. The first decomposition step involves release of alkyl halide to form the [Pd(ESDT)X]n (X = Cl or Br) intermediates, which successively dec ompose, finally giving palladium.