An ansa-zirconocene bearing methyl substituents at all positions adjacent to the bridgehead [(âC(Ph)HC(Ph)Hâ)(η5-2,5-Me2C5H2)2ZrCl2] (4) was prepared in high yields (78%) through the reductive dimerization of 1,4-dimethyl-6-phenylfulvene utilizing ZrCl2·DME generated in situ. The structure of 4 was subsequently confirmed using X-ray crystallography. 4 exhibited excellent catalytic performance with regard to 1-decene oligomerization, which was carried out with the intention of preparing lubricant base stocks. High activities (21 à 106 g molâ1 Zr hâ1 activity; TON = 150â000; TOF = 42 sâ1) were observed at temperatures as high as 120 °C and the oligomer distribution was appropriate for lubricant application. The simulated distillation (SIMDIS) data confirmed that a wide range of oligomers were formed, ranging from the dimer (2-mer) to 20-mer. A minimal amount of the dimer and oligomers larger than the 10-mer was formed (13 and 25 wt%, respectively). Alternatively, a typical unbridged complex such as (η5-nBuC5H4)2ZrCl2 primarily produced dimers (54 wt%), whereas the ansa-zirconocene (EBI)ZrCl2 primarily produced oligomers larger than 10-mer (62 wt%). The methyl substituents at the positions adjacent to the bridgehead in 4 played a significant role in the catalytic performance.
                                    通过1,4-二甲基-6-苯基富烯的还原二聚化,利用原位生成的ZrCl2·
DME,制备了在所有相邻位置都带有甲基取代基的ansa-
锆茂[(–C(Ph)HC(Ph)H–)(Μ5-2,5-Me2C5H2)2ZrCl2] (4),且收率很高(78%)。随后利用X射线晶体学确认了4的结构。4在1-
癸烯低聚反应中表现出优异的催化性能,该反应的目的是制备润滑油基础油。在高达120°C的温度下观察到高活性(21×106 g mol–1 Zr h–1活性;TON = 150000;TOF = 42 s–1),且低聚物的分布适合润滑油应用。模拟蒸馏(SI
MDIS)数据证实,形成了从二聚体(2-mer)到20-mer的各种低聚物。形成了极少量的二聚体和大于10-mer的低聚物(分别占13%和25%)。另外,典型的非桥联络合物(Μ5-nBuC5H4)2ZrCl2主要产生二聚体(54%),而ansa-
锆茂(EBI)Zr