Transition Metal Complexes with Sulfur Ligands, IV. Synthesis and Reactions of Mo (IV) Complexes with the Tetradentate Thioether-thiol Ligand 2,3,8,9-Dibenzo-1,4,7,10-tetrathiadecane

Synthesis and characterization of non-oxo Mo(IV) complexes with the tetradentate thioether-thiol ligand 2,3,8,9-dibenzo-1,4,7,10-tetrathiadecane(dttd-H2) are reported. MoCl4(THF)2 reacts with dttd-H2 in THF at room temperature to give the paramagnetic (2.61 BM, 295 K) [Mo(dttd)Cl2]. The chlorine ligands in [Mo(dttd)Cl2] can be substituted by sulfur ligands yielding diamagnetic complexes as [Mo(dttd)(CeH4S2)], [Mo(dttd)(SC2H4S)] and [Mo(dttd)(SC2H5)2]; with Na2S, NaHS or H2S, the di-μ-sulfido bridged complex [(dttd)Mo(S)2Mo(dttd)] is obtained. The reduction of [Mo(dttd)Cl2] by various reducing agents in the presence of CO or NO yields labile carbonyl and nitrosyl species in solution. In contrast to [Mo(dttd)Cl2], the complexes with MoSe cbromophores showed no reactivity to CO or NO under reducing conditions.