Development of new rare earth metal polymerization catalysts

新型稀土金属聚合催化剂的研制

基本信息

批准号：
13440203
负责人：
HOU Zhaomin
金额：
$ 3.58万
依托单位：
RIKEN (The Institute of Physical and Chemical Research)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2004
项目状态：
已结题

项目摘要

1.1,4-Cis stereospecific polymerization of 1,3-butadiene by samarocene catalystsThe C_5Me_5R-ligated samarocene(II) complexes, (C_5Me_4R)_2Sm(THF)_x(1, R=Me ; 2, R=Et ; 3, R=i-Pr, 4, R=n-Bu, 5 ; R=TMS ; x=1 or 2), in combination with modified methylaluminoxane(MMAO) were examined in cyclohexane with respect to their catalytic performances for the polymerization of butadiene. Complexes 2-5 showed considerable promotion in both catalytic activity and regularity of the resulting polymer as compared to parent 1 : activity,3>>5〜4>2>1 ; 1,4-cis selectivity at 50℃,3〜5>4>2>1.2.1,4-Cis stereospecific polymerization of 1,3-butadiene by cationic rare earth metallocene catalystsCationic metallocene complexes[(C_5Me_5)_2Ln][B(C_6F_5)_4](Ln=Pr, Nd, Gd) in combination with ^iBu_3Al efficiently induce highly 1,4-cis specific polymerization of butadiene. The activity of the Gd complex/^iBu_3Al system is high enough to exhibit good catalytic activity even at low temperature. Polymerization at -78℃ gave … More polybutadiene with nearly perfect 1,4-cis microstructure (>99.9%) with sharp molecular weight distribution (M_w/M_n=1.45) and in reasonable yield.3.Synthesis, Structural Characterization, and Novel Catalysis of Rare Earth Alkyl Complexes Bearing Silylene-Linked Cyclopentadienyl-Phosphido LigandsThe reactions of Ln(CH_2SiMe_3)_3(THF_2)(Ln=Y, Yb, Lu) with 1 equiv of Me_2Si(C_5Me_4H)(PHR)(R=Ph, Cy) afforded the first silylene-linked cyclopentadienylphosphido rare earth alkyl complexes, [Me_2Si(C_5Me_4)(μ-PR)Ln(CH_2SiMe_3)]_2. In contrast with the analogous cyclopentadienyl-amido and metallocene complexes, these complexes adopt a dimeric structure through phosphide bridging, while the alkyl ligand is placed in a terminal position. Owing to their unique steric and electronic ligand environments, most of these complexes showed much higher activity for the polymerization of ethylene and hydrosilylation of olefins than that of the conventional metallocene or amido analogues. Moreover, when treated with [Ph_3C][B(C_6F_5)_4], these complexes showed extremely high regio- and stereoselectivity for the 3,4-polymerization of isoprene, which yielded the isotactic (>99% mmmm) 3,4-poly(isoprene) selectively. This is the first example of stereospecific 3,4-polymerization of isoprene. Less

三茂催化剂催化1,3-丁二烯的1.1,4-顺式立体定向聚合C_5Me_5R-连接的二茂(II)配合物, (C_5Me_4R)_2Sm(THF)_x(1, R=Me ; 2, R=Et ; 3, R= i-Pr，4，R=n-Bu，5；R=TMS； 2) 与改性甲基铝氧烷 (MMAO) 组合，在环己烷中检查其对丁二烯聚合的催化性能，与母体 1 相比，配合物 2-5 在所得聚合物的催化活性和规整性方面均显示出显着的提升：活性,3>>5〜4>2>1 ; 1,4-顺式选择性50℃,3～5>4>2>1.2.1,4-顺式1,3-丁二烯阳离子稀土茂金属催化剂阳离子茂金属配合物[(C_5Me_5)_2Ln][B(C_6F_5)_4](Ln= Pr, Nd, Gd) 与 ^iBu_3Al 结合有效诱导高度 1,4-顺式特异性聚合Gd络合物/^iBu_3Al体系的活性足够高，即使在低温下也能表现出良好的催化活性，得到具有近乎完美的1,4-顺式微观结构（>99.9%）的聚丁二烯。分子量分布（M_w/M_n=1.45）和合理的收率。3.稀土的合成、结构表征和新型催化带有亚甲硅基连接的环戊二烯基磷配体的烷基配合物Ln(CH_2SiMe_3)_3(THF_2)(Ln=Y, Yb, Lu)与1当量的Me_2Si(C_5Me_4H)(PHR)(R=Ph, Cy)反应得到第一个亚甲硅基连接的环戊二烯基磷基稀土烷基配合物，[Me_2Si(C_5Me_4)(μ-PR)Ln(CH_2SiMe_3)]_2 与类似的环戊二烯基酰胺基和茂金属配合物相比，这些配合物通过磷化物桥接采用二聚结构，而烷基配体位于末端。由于其独特的空间和电子配体环境，大多数这些配合物表现出更高的聚合活性。此外，当与[Ph_3C][B(C_6F_5)_4]结合时，这些配合物对异戊二烯的3,4-聚合表现出极高的区域选择性和立体选择性。选择性地产生全同立构 (>99% mmmm) 3,4-聚(异戊二烯) 这是第一个例子。异戊二烯的立体定向3,4-聚合反应较少。