[Flu(Me)_2CCp]_2Yb(μ-Br)_2Li(THF)_2·THF的合成和晶体结构

Synthesis and Crystal Structure of Bis[[2-(fluoren-9-yl)isopropyl] Cyclopentadienyl] Ytterbium-di-μ-bromo-bis(tetrahydrofuran)lithium Monotetrahydrofuran

为考察取代环戊二烯基或桥联环戊二烯基有机稀土化合物的性质,研究了碳桥联芴基环戊二烯基配体与卤化稀土的反应,其中,[2-(9-芴基)异丙基]环戊二烯基锂[Flu(Me)2CCpLi]与三溴化镱(YbBr3)在四氢呋喃(THF)中反应,分离得到了标题配合物[Flu(Me)2CCp]2Yb(μ-Br)2Li(THF)2.THF。X射线单晶结构测定表明配合物属单斜晶系,空间群为P2(1)/n,晶胞参数为:a=1.4676(3)nm,b=1.2618(4)nm,c=2.9736(9)nm,β=98.172(18)°,Z=4,V=5.451(2)nm3,Mr=1098.84,Dc=1.339 mg.m-3,R=0.0695,wR=0.1721。中心Yb原子分别与两个环戊二烯基和两个溴原子成键,形成扭曲的四面体配位构型。Yb-Br1和Yb-Br2键长分别为0.2765(1)和0.2738(1)nm,两个环戊二烯基平面的夹角为125.7°,中心Yb原子与两个环戊二烯基环中心的平均距离分别为0.232和0.231 nm。

The title complex, [ Flu （ Me ） 2 C Cp ] 2Yb （μ- Br）2Li（THF）2·THF, was isolated from the reaction of [Flu（Me）2CCpLi] and YbBr3 in THF. X-ray diffraction analysis indicates that the crystal of the complex is of monoclinic, space group P2 （ 1 ）/n, with α = 1.4676（3） nm, b = 1.2618（4） nm, c = 2.9736（9） nm, β=98.172（18）°, V=5.451（2） nm^3, Mr= 1098.84, Z=4, Dc=1.339mg·m^-3, R=0.0695, and wR = 0. 1721. The complex is an asymmetric μ-Br-bridged dimer containing lanthanide and alkali metal elements. The coordination polyhedron around the Yb atom is a distorted tetrahedron defined by the centroids of the cyclopentadienyl rings and the two Br atoms. The Yb-Br1 and Yb-Br2 distances are 0. 2765 （1） and 0. 2738 （1） nm, respectively. The angle of two planes of the cyclopentadienyl rings is 125.7°. The Yb-ring centroid （Cn） distances are 0. 232 and 0.231 nm, respectively.