Ytterbium Ate Complexes with 1,2-Bisimine Ligand: Paramagnetic NMR

The reaction of [(dpp-bian)Yb(DME) 2 ] with one equivalent of dpp-bian and one equivalent of potassium or sodium gave the ate complexes [(dpp-bian) 2 Yb][K(DME) 4 ] and [(dpp-bian) 2 Yb][Na(THF) 6 ]. The reaction of [(dpp-bian)YbI(DME)] 2 with potassium cyclopentadienide (CpK) led to the complex [{(dpp-bian)CpYb(μ-Cp)· K(Et 2 O) 2 } 2 (μ-Cp) 2 Yb(THF) 2 ]. In all three compounds, the redox-active dpp-bian exhibits a dianionic state. Yb 3+ cations in the prepared compounds determine their paramagnetism. Despite this, resolved 1 H and 13 C NMR spectra were obtained for [(dpp-bian) 2 Yb][K(DME) 4 ] and [(dpp-bian) 2 Yb][Na(THF) 6 ] in THF- d 8 , which made it possible to assign observed signals. The new compounds were characterized by IR and NMR spectroscopy and elemental analysis (C, H, N). The molecular structure of the prepared complexes was determined by X-ray diffraction