Preparation and structures of enantiomeric dinuclear zirconium and hafnium complexes containing two homochiral N atoms, and their catalytic property for polymerization of rac-lactide
作者:Minggang Hu、Mei Wang、Hongjun Zhu、Lu Zhang、Hui Zhang、Licheng Sun
DOI:10.1039/c001148g
日期:——
coordination of the unsymmetric tertiary amine ligands to the metal centers. Enantiomeric dinuclear complexes 2 and 3 both undergo spontaneous resolution during crystallization. The molecular structure of each enantiomer of 2 and 3, as well as the structure of 1, was determined by X-ray analysis and the circular dichroism spectra of N(R)N(R)-2 and N(S)N(S)-2 were studied. The racemates of 2 and 3 catalyzed controlled
羟基和 苯氧基桥联双核 锆 和 铪胺-吡啶-双(酚盐)配体(H 2 L)的配合物2和3由钠2升 和 氯化锆4 在0.5当量的 水 在 四氢呋喃,而H 2 L与碳酸氢钠 然后用 氯化锆4 在新鲜蒸馏的 四氢呋喃 给出了八坐标 bis(杀菌剂)单核复合物L 2 Zr(1)。两个同手性ñ在不对称的叔胺配体与金属中心配位的情况下,在每个络合物中产生原子。对映体双核配合物2和3在结晶过程中均经历自发的拆分。的各对映异构体的分子结构2和3,以及结构1,通过X射线分析和N(圆二色光谱测定- [R)N(- [R - )2和N(小号)N(小号)-2进行了研究。2和3的外消旋体催化rac的受控聚合--丙交酯就分子量对转化率的线性而言,以高收率和窄的多分散性形成富含等规度的聚丙交酯。