New Rare Earth Metal Bis(alkyl)s Bearing an Iminophosphonamido Ligand. Synthesis and Catalysis toward Highly 3,4-Selective Polymerization of Isoprene
作者:Shihui Li、Wei Miao、Tao Tang、Weimin Dong、Xuequan Zhang、Dongmei Cui
DOI:10.1021/om700945r
日期:2008.2.1
η2-chelated NPN ligand and two cis-located alkyl groups, adopting tetrahedron geometry. The scandium complex [(NPNPh)Sc(CH2SiMe3)2(THF)] in combination with [PhNHMe2][B(C6F5)4] and AliBu3 forms the first non-Cp-ligated rareearth metal based catalyst system to provide extremely high activity and 3,4-selectivity for the polymerization of isoprene. The resultant high molecular weight polymer (Mn = 99 × 104)
新的稀土金属双(烷基)配合物[(NPN Ph)Ln(CH 2 SiMe 3)2(THF)](NPN Ph:N(Ph)PPh 2 NC 6 H 2 Me 3 -2,4,6 ; Ln为钪(图3a),Ln为Y(图3b),LN =路(图3c))和[(NPN PY)钪(CH 2森达3)2(THF)](NPN PY = N(PY)PPH 2 ═ NC 6 H 2 Me 3 -2,4,6)(3d))是通过稀土金属三(烷基)与相应的亚氨基膦胺之间的质子分解反应制备的。配合物3a - d是THF溶剂化物的类似单体。每个金属离子坐标到η 2 -chelated NPN配体和2分的顺式-位于烷基,采用四面体几何形状。complex配合物[(NPN Ph)Sc(CH 2 SiMe 3)2(THF)]与[PhNHMe 2 ] [B(C 6 F 5)4 ]和Al i Bu 3的组合形成第一个非Cp连接的稀土金属基催化