Synthesis, Structure, and Photoluminescent Properties of [{Tb(Me2Si(NMes)2)(thf)2}2(μ-BH4)2]

The complex [{Tb(Me2Si(NMes)2)(thf)2}2(μ-BH4)2] (1) has been synthesized by the reaction of [{Tb(Me2Si(NMes)2)(thf)2}2(μ-Cl)2] (4; Mes is mesityl) with an excess of NaBH4 in THF. It has turned out that the complete replacement of the chloride ligands by BH4− occurs after heating the reaction mixture at 70°C for two weeks. When the reaction was stopped after five and seven days, polycrystalline [{Tb(Me2Si(NMes)2)(thf)2}2(μ-BH4)x(μ-Cl)2 – x] phases (x ⁓ 1.2 (2); 1.4 (3)), as well as single crystals corresponding to these compositions, were isolated. The structures of 1–3 have been determined by single-crystal X-ray diffraction. The photoluminescent properties of solutions of these complexes in THF have been studied. The study demonstrates that the substitution of 
 for Cl– leads to an increase in the luminescence quantum yield.