Triazolecarboxamidate Donors as Supporting Ligands for Nickel Olefin Polymerization Catalysts
Triazolecarboxamidate Donors as Supporting Ligands for Nickel Olefin Polymerization Catalysts
复制标题
三唑甲酰胺酯供体作为镍烯烃聚合催化剂的支持配体
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
L. Do
中科院分区：
文献类型：
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作者：
Dawei Xiao;L. Do
为了增加用于构建烯烃聚合催化剂的双核平台的结构多样性，我们正在探索具有非醇氧/酚氧桥基的新配体设计。在本研究中，我们证明了1，2，3-三氮唑-4-氨基甲酸酯供体是镍的优良的N，N-螯合剂，并且容易结合二次金属离子。我们发现，空间大体积的三氮唑甲酰胺镍配合物具有催化乙烯均聚的活性，可以得到每1000个碳原子中约有80-130个支链的低相对分子质量聚乙烯。在某些情况下，锌盐添加到镍配合物中会导致催化剂的抑制，我们将其归因于形成了催化不活跃的混合金属物种。为了避免这个问题，我们预计进一步细化三氮唑甲酰胺配体可以提供离散的异双金属络合物，这些络合物将用作具有独特反应模式的单位催化剂。
To increase the structural diversity of dinucleating platforms that are used in the construction of olefin polymerization catalysts, we are exploring new ligand designs that feature non-alkoxide/phenoxide bridging groups. In the current study, we demonstrate that 1,2,3-triazole-4-carboxamidate donors are excellent N,N-chelators for nickel and can readily bind secondary metal ions. We found that sterically bulky nickel triazolecarboxamidate complexes are active as ethylene homopolymerization catalysts and can afford low molecular weight polyethylene with about 80–130 branches per 1000 carbon atoms. The addition of zinc salts to our nickel complexes led to catalyst inhibition in some cases, which we have attributed to the formation of catalytically inactive mixed-metal species. To circumvent this problem, we anticipate that further elaboration of the triazolecarboxamidate ligand could provide discrete heterobimetallic complexes that will be useful as single-site catalysts with unique reactivity patterns.