Syntheses and electrochemistry of metal complexes of a bulky pyridine-thiolate ligand

Article abstract of DOI:10.1016/S0277-5387(97)00098-3

Reactions of Li(tBuL-NS) (lithium bis(4-t-butylphenyl)-2-pyridylmethanthiolate(1-)) with MCl₂ (M = Ni, Zn, Pt) afforded the respective M(tBuL-NS)₂ complexes in good yields. Treatment of CuCl₂, Cu(OTf)₂ (OTf = triflate) and PdCl₂(PhCN)₂ with Li(tBuL-NS) led to the formation of the dimeric compounds [Cu(tBuL-NS)Cl]₂·2H₂O, Cu₂(tBuL-NS)₃(OTf) and [Pd(tBuL-NS)Cl]₂, respectively. The interaction of Li(t-BuL-NS) with [Ru(CO)₂Cl₂]_n, [Rh(COD)Cl]₂ (COD = 1,5-cyclooctadiene) and Re(CO)₅Cl gave cis-Ru(tBuL-NS)₂(CO)₂, Rh(tBuL-NS)(COD) and Re(tBuL-NS)(CO)₄, respectively. The structure of Rh(tBuL-NS)(COD) has been established by X-ray crystallography. The geometry around Rh is square planar with Rh-N and Rh-S distances of 2.114 (5) and 2.250 (2) A, respectively. Reaction of Ni(PMe₃)₂(CH₃)Cl with Li(tBuL-NS) afforded Ni(tBuL-NS)(PMe₃)CH₃, which undergoes CO insertion to give the acyl complex Ni(tBuL-NS)(PMe₃)(COCH₃). The cyclic voltammogram of Pt(tBuL-NS)₂ exhibits a reversible 1-electron couple at 0.3 V vs ferrocenium-ferrocene, which is assigned as the ligand-centered oxidation.