Complex salts and heterometallic complexes derived from bis(1-ethoxycarbonyl-1-cyanoethylene-2,2-dithiolato)metalate(II) ions: synthesis and properties

Molecular electrical conducting properties of a series of new complex salts, [n-Pr4N]2[M(ecda)2] and heterobimetallics, VO[M(ecda)2] [M=Ni(II), Cu(II), Zn(II) or Cd(II); ecda2−=1-ethoxycarbonyl-1-cyanoethylene-2,2-dithiolate] and Cu[Zn(ecda)2] that have been synthesized and characterized by elemental analysis, solution conductivity and magnetic susceptibility measurements and relevant spectroscopies [IR, UV–VIS, EPR, 1H and 13C NMR] are described. Complete quenching of paramagnetism at room temperature showed presence of strongly antiferromagnetically coupled Cu(II) ions in Cu[Zn(ecda)2]. Considerably low values of magnetic moment and feature of EPR spectra in the remaining heterobimetallics containing VO(IV), Ni(II) and Cu(II) showed involvement of some sort of metal–metal interaction in these species. All of the compounds exhibited semiconducting behaviour in the range of 293–393 K with σrt=10−12 to 10−8 S cm−1.