X-ray diffraction studies. In all five complexes, the naphtholate rings twist in the same direction from the plane of the pyridine or thiophene linker, to give rise to Cs-symmetric (non crystallographic) structures. Compounds 1–9 are single-site initiators for the ring-opening polymerization (ROP) of racemic lactide (rac-LA) at 20 °C, affording poly(lactides)s (PLAs) with relatively narrow polydispersities
钪,
钇 和
镧镧 三齿支持的配合物 双(邻甲
硅烷基取代的
萘甲酸酯)-供体
配体(ONO SiPh3 } 2-和ONO Si t BuMe2 } 2−,供体=2,6-
吡啶; OSO SiPh3 } 2−,供体=2,5-
噻吩)通过相应的原
配体OZO SiR3 } H 2和Ln [N(SiHMe 2)2 ] 3(THF)n前体。的固态结构ONO SiPh3 } La [N(SiHMe 2)2 ](THF)(3),ONO Si t BuMe2 } Ln [N(SiHMe 2)2 ](THF) (Ln = SC,4 ;ÿ,5)和OSO SiPh3 } Ln [N(SiHMe 2)2 ](THF) (Ln = SC,7 ;啦啦(9)已经通过单晶X射线衍射研究确定。在所有五个综合体中,
萘甲酸酯环从
吡啶或
噻吩连接子的平面沿相同方向扭曲,从而形成C s对称(非晶体学)结构。化合物1–9是外消旋体的开环聚合(ROP)的单中心
引发剂