Interaction of zinc and cadmium Bis(benzothiazole-2-thiolates) with nitrogen bases
Abstract
The reactions of polymeric [Zn(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(1) and 2.063(4)Å in 1 and 2.310(13) and 2.096(4)Å 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)Å and the corresponding mean Cd–N(py) is 2.334(4)Å. 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.