Mono- and bis(cyclopentadienyl)hafnium(IV) derivatives with heterocyclic dithiocarbamates

Some new mono- and bis(cyclopentadienyl)hafnium(IV) derivatives of dithioca rbarnate ligands, in which one heterocyclic ring (thiadiazole) is attached to nitrogen, have been prepared by the reactions of bis(cyclopentadienyl)ha fnium(IV) chloride with potassium salts of dithiocarbamic acids in 1:1 and 1:2 molar ratios, respectively, in refluxing tetrahydrofuran. The derivativ es Of types (C5H5)(2)HfCl(DTC) and (C5H5)HfCl(DTC)(2) have been characteriz ed by elemental analysis, conductivity measurements and spectral (IR, H-1 N MR) studies. All the complexes are monomeric and non-electrolyte in nature. IR and NMR spectral data of these complexes show the bidentate behaviour o f ligands and five-coordinate and six-coordinate structures for bis(cyclope ntadienyl)hafnium(IV) and mono(cyclopentadienyl)hafnium(IV) derivatives, re spectively.