Übergangsmetallkomplexe mit Schwefelliganden, LXXXV. / Transition-Metal Complexes with Sulfur Ligands, LXXXV.

Ni(II) salts and the tetradentate thioether-thiolate ligand ′S4-C2′2- (= 1,2-bis(2-mercaptophenylthio)ethane(2-)) yield [Ni(′S4-C2′)]x (1), that also forms when Na2[Ni(′S2′ )2] (′S22-′ = o-benzenedithiolate(2-)) is alkylated by 1,2-dibromoethane. In boiling pyridine 1 adds two solvent molecules and gives pseudooctahedral [Ni(pyr)2(′S4-C2′ )] (2) which was characterized by X-ray structure determination. Reaction of 1 with PMe3 yields [Ni(PMe3)(′S4-C2′)] (4). X-ray structure determination of 4 showed that the Ni center is surrounded by one P and four S atoms in a distorted tetragonal pyramid in which the P atom, one thioether S atom and both of the thiolate S atoms form the base while the second thioether S atom occupies the apical position. Reaction of 1 with n-BuLi leads to removal of the C2H4 bridge of the ′S4-C2′2- ligand and formation of Li2[Ni(′S2′)2].When [Ni(acac)2]3 is reacted with ′buS4-C2′2 (= 1,2-bis(3,5-ditertiarybutyl-2-mercaptophenylthio)ethane(2-)) which is analogous to ′S4-C2′2-, the trinuclear [Ni(′buS4-C2′)]3 (3) forms. 3 · THF was characterized by X-ray structure determination. It contains one tetrahedrally distorted and two planar [NiS4] cores that are connected via the C2H4 groups of the ligands such that a macrocycle forms. PMe3 cleaves 3 to give mononuclear [Ni(PMe3)(′buS4-C2′)] (5). Due to its lability, it was characterized only by spectroscopic methods.