New nickel complexes with an S4 coordination sphere; synthesis, characterization and reactivity towards nickel and iron compounds

Three new nickel complexes have been synthesized with the ligands Hbss (4-mercapto-2-thia-1-butylbenzene) and Hbsms (2-(benzylsulfanyl)-2-methyl-1-propanethiol). [Ni(bss)2] is a mononuclear complex with an S4 coordination environment. [Ni3(bss)4](BF4)2 and [Ni3(bsms)4](BF4)2 are linear trinuclear complexes that can be synthesized either directly from the ligands Hbss and Hbsms in a reaction with Ni(BF4)2, or via the mononuclear complexes [Ni(bss)2] and [Ni(bsms)2] in a reaction with Ni(BF4)2. These reactions have been monitored with ligand field spectroscopy. Crystals suitable for X-ray diffraction were obtained for [Ni3(bss)4](BF4)2. The complex crystallizes in the space group P21/c. The nickel centers are in a square-planar environment; two peripheral nickel centers with an S2S2′ (S=thiolato; S′=thioether) coordination environment and the central nickel ion with an S4 coordination environment.