A new dianionic guanidinate bridged diamide ytterbium(Ⅲ) complex {[Me2Si(NPh)2]2Yb[(NiPr)2CN(SiMe3)2]}{Li(THF)2}2 was synthesized by the reaction of bisguanidinate ytterbium chloride [(SiMe3)2NC(NiPr)2]2Yb(μ-Cl)2Li(THF)2 with silylene-bridged diamide lithium PhLiNSiMe2NLiPh.The complex was characterized by elemental analysis and IR.The molecular structure was further determined by X-ray diffraction techniques.The crystals are monoclinic,space group p 21/c,a=14.0001(8),b=17.6808(9),c=24.9565(16),β=95.994(3),V=6143.8(6)3,Dc=1.287 g/cm3,Z=4.
A homoleptic lanthanide guanidinate complex [（CH2）5NC（NiPr）2]3Yb was synthesized by the metathesis reaction of lithium guanidinate with anhydrous YbCl3 in 3∶1 molar ratio in THF.Its crystal structure was determined by X-ray diffraction.The crystallographic data:C36H72N9Yb,Mr=804.07,orthorhombic,space group P212121（#19）,a=10.3168（7）,b=11.443（7）,c=35.5649（2）?,V=4199.1（5）?3,Z=4,Dc=1.272 g/cm3,F（000）=1684.00,T=193.1K,λ（MoKα）=0.7107?,μ=22.61 cm-1,R=0.040,wR=0.126 for 8653 observed reflections with（I>3.00 σ（I））.The ytterbium is six-coordinate by six nitrogen atoms of three chelation bidentate guanidinate ligands.
Cp2Yb·2THF reacts with CpNa in 1:1 molar ratio in THF at 40℃ for 2 h, and the in situ generated ani-onic divalent complex NaYbCp3(THF)n reacts further with an excess of CpH at 40℃ for 48 h, after work-up, affording the trivalent anionic ytterbium complex [Na(THF)2(μ2-η5-Cp) (η5,η5,η1-Cp3Yb)(THF)]n (1) by oxidation reaction of Cp2Yb with CpH. Crystal structure determination reveals that com-plex 1 has one-dimension polymeric chains of distinct Na(THF)2(μ2-η5-Cp)(η5,η5,η1-Cp3Yb)(THF) units, which were formed by the coordination of the bridging Cp ligand with Cp3Yb·THF and Na(THF)2 in η5,η5 mode via self-assembly.
