The development of group IV catalysts for homogeneous olefin polymerizations is crucial for both industrial and academic research. In this study, we present the synthesis and full characterization (¹H NMR, ¹³C NMR, Elem. Anal. and X-ray) of a new class of oxazoline-amine zirconium complexes. When used in combination with Ph₃C⁺⁻B(C₆F₅)₄ as the cocatalyst in the absence of scavenger, these complexes show high activity (up to 29.5 kg/(mol·min·atm)) in ethylene homopolymerization giving PE with M_w up to 392.4 kg/mol. On average, these complexes generate less than one polymer chain per catalyst, and negligible olefinic end groups were observed by NMR, both suggesting the absence or lack of chain transfer during polymerization. Furthermore, these complexes are also effective in ethylene/1-octene copolymerization, showing activity up to 42.9 kg/(mol·min·atm) and octene enchainment ratio up to 25.2 mol%. Gradually increasing the reaction time from 1 to 15 min leads to an increase in polymer M_w, chains/cat (up to 14.4) and a decrease in activity. Octene incorporation ratio increases from 12.6 to 17.9 mol% over reaction time (1 to 5 min) at 50 °C, likely suggesting mass transfer limitations at long reaction times. Increasing temperature from 50 °C to 90 °C leads to reduced activity and product M_w (> 5 ×), and increased chains/cat (≈5 ×) in the copolymerization. Olefinic end group analysis by ¹H NMR suggests β-H elimination/transfer occurs after octene 2,1-insertion (vinylene; predominant), ethylene insertion (vinyl) and octene 1,2-insertion (vinylidene) at high temperatures.

用于均相烯烃聚合的 IV 族催化剂的开发对于工业和学术研究都至关重要。在这项研究中，我们介绍了一类新的恶唑啉-胺锆配合物的合成和完整表征（¹ H NMR、^{13 C NMR、元素分析和 X 射线）。}当在没有清除剂的情况下与 Ph 3 C +− B(C 6 F 5 ) 4 作为助催化剂结合使用时_，这些^络合物在_乙烯均_聚反应_中表现出高活性（高达 29.5 kg/(mol·min·atm)），给出PE_与Mw高达 392.4 千克/摩尔。平均而言，这些络合物每个催化剂产生少于一个聚合物链，并且通过 NMR 观察到可忽略不计的烯烃端基，这两者都表明在聚合过程中不存在或不存在链转移。此外，这些配合物在乙烯/1-辛烯共聚中也很有效，显示出高达 42.9 kg/(mol·min·atm) 的活性和高达 25.2 mol% 的辛烯链率。将反应时间从 1 分钟逐渐增加到 15 分钟会导致聚合物M _w增加，链/催化剂（高达 14.4）和活性降低。在 50 °C 下，随着反应时间（1 至 5 分钟），辛烯掺入率从 12.6 mol% 增加到 17.9 mol%，这可能表明长反应时间下的传质限制。将温度从 50 °C 升高到 90 °C 会导致活性和产物降低M _w (> 5 ×)，并在共聚中增加 chains/cat (≈5 ×)。^通过1 H NMR进行的烯烃端基分析表明，β-H 消除/转移发生在高温下辛烯 2,1-插入（亚乙烯基；主要）、乙烯插入（乙烯基）和辛烯 1,2-插入（亚乙烯基）之后。