INTERACTION OF ZINC AND CADMIUM BIS(BENZOTHIAZOLE-2-THIOLATES) WITH NITROGEN BASES

The reactions of polymeric [Zn(C7H4NS2)2] and [Cd(C7H4NS2)2] with pyridine (py), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen) lead to the formation of mononuclear adducts which have been characterized by elemental analysis and infrared spectroscopy. The complexes [Zn(C7H4NS2)2(py)2] 1, [Zn(C7H4NS2)2(bipy)] 2 and [Cd(C7H4NS2)2(py)2] 3 were structurally characterized by X-ray crystallography. Adducts 1 and 2 have distorted-tetrahedral ZnN2S2 Cores. The zinc ions are co-ordinated to the two exocyclic S atoms of the benzothiazole-2-thiolates and to two nitrogen atoms from the py or bipy base. The Zn-S and Zn-N bond distances are 2.324(l) and 2.063(4) angstrom in 1 and 2.310(13) and 2.096(4) angstrom in 2. The complex [Zn(C7H4NS2)2(phen)] was found to be isomorphous to 2. Adduct 3 shows a distorted-octahedral CdN4S2 unit formed by two bidentate S,N benzothiazole-2-thiolates and two cis pyridine nitrogen atoms. The two exocyclic S atoms are located at the axial positions. The mean Cd-S and Cd-N bonds of the bidentate ligands in 3 are 2.706(10) and 2.422(30) angstrom and the corresponding mean Cd-N (py) is 2.334(4) angstrom. The infrared spectra of the adducts in the range 650-200 cm-1 are discussed in the light of the known structures. The thermal degradation of complexes 1-3 affords ZnS or CdS.