稀土-锂双金属配合物的研究——(LaCl)DME(μ_2-Cl)_5(μ_3-Cl)(La·DME)Li(THF)_2的合成及其晶体结构  

Study of Bimetallic Complexes of Rare Earth-Lithium Synthesis and Crystal Structure of the (LaCl)DME(μ2-Cl)_5(μ3-Cl) (La·DME)Li(THF)_2

作　　者：李祥高[1] 刘静芝[1] 胡宁海[1] 金钟声[1] 刘国智[1] 

机构地区：[1]中国科学院长春应用化学研究所

出　　处：《化学学报》1989年第12期1191-1196,共6页Acta Chimica Sinica

摘　　要：在稀土有机化学中,[Cp_2LnCl]_2和[Cp_2LnCl_2LiL_2][Cp为取代或未取代的环戊二烯基,Ln为稀土离子(III),L为Lewis碱]型化合物是重要的中间物。对含锂烷基、芳基或烯丙基稀土化合物的研究也有着重要的意义。这类分子中含有型桥键结构。由于这类化合物难于结晶及其不稳定性,故很难进行系统的研究。 Rossmanith首先发现了NdCl_3-LiCl-THF溶液的存在。李毅用这一溶液很方便地合成了几个轻稀土-锂双金属有机化合物。但是,在稀土配位化学中,对氯化稀土-氯化锂配合物的研究还很少,对LnCl_3LiCl-THF溶液的认识也有待深化。本文合成了组成为(LaCl)DME(μ_2-Cl)_5(μ_3-Cl)(La·DME)Li(THF)_2的新型桥式链状配合物,并测定了晶体结构。这种类型的稀土双金属配合物尚未见报道。The reaction between LaCl_3 and LiCl in THF at room temperature, with hexane as precipitant and glycol dimethyl ether as complexing agent, has been studied. A complex with the composition of (LaCl)DME(μ_2-Cl)_5(μ_3-Cl)(La·DME)Li(THF)_2 has been synthesized, its structure was studied by single crystal X-ray diffraction technique. The diffraction intensities were collected at about —100℃. The complex belongs to the triclinic space group P1 with α=11.123(3), 6=16.564(5), c=8.653(3)A, α=95.16(3), β=95.63(3), γ=74.71(2)°; Z=2. The final R value is 0.0303. The molecule presumes to have a chain conformation in which the La^(3+)ions are linked by μ_2and μ_3-bridged chlorine atoms alternatively. The avorage bond lengths of La—Cl in μ_3-chloro-bridge bond and μ_2-chloro-bridge bond are 2.972 and 2.886A respectively. The average bond lengths of La—0 and Li—0 are 2.611 and 1.927A respectively.

关 键 词：稀土 镧 锂 双金属配合物 合成 晶体结构 

分 类 号：O614.331[理学—无机化学] O614.112[理学—化学]