GREEN BIS-(2-IMINOISOPROPYL-THIOPHENOLATO )NICKEL(II) AND OTHER SIMILAR NI-II COMPLEXES

The compounds [Ni-II(iitp)(2)] 1 (iitp=2-iminoisopropyl-thiophenolate) , [Ni-2(II)(imptp)(2)]. 2CH(3)OH 2, a dinuclear compound with an Ni-Ni distance of 276 pm, and [PPh(4)].[Ni-II(imptp)(SCN)] 3 (imptp=2-(2-im inopentane-4-on)-thiophenolate) have been prepared by the reaction of nickel(II)-acetate-tetrahydrate with 2-iminoisopropyl-thiophenole and 2-(2-iminopentane-4-on)-thiophenole in methanol, respectively. They ha ve been characterized by single-crystal X-ray structure analysis and o ther physical methods. The redox behaviour of 1-3 has been studied in detail (chemically as well as by cyclovoltammetry and ESR spectroscopy ). Particularly interesting are the electronic properties of 1 and its reduction with NaBH4 and the following reaction of the product with O -2 The complexes are model compounds for some Ni-containing enzymes. F or details of the crystal structure determination see ''Inhaltsubersic ht''.