Catalyst-transfer polymerization (CTP) is a living, chain-growth method for accessing conjugated polymers with control over their length and sequence. Typical catalysts utilized in CTP are either Pd or Ni complexes with bisphosphine or N-heterocyclic carbene ancillary ligands. More recently, diimine-ligated Ni complexes have been employed; however, in most cases nonliving pathways become dominant at high monomer conversions and/or low catalyst loading. We report herein an alternative Ni diimine catalyst that polymerizes 3-hexylthiophene in a chain-growth manner at low catalyst loading and high monomer conversion. In addition, we elucidate the chain-growth mechanism as well as one chain-transfer pathway. Overall, these studies provide insight into the mechanism of conjugated polymer synthesis mediated by Ni diimine catalysts.

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镍二亚胺催化剂介导的噻吩催化剂转移聚合的机理研究

催化剂转移聚合（CTP）是一种活性的，链增长的方法，用于控制共轭聚合物的长度和顺序，以获取共轭聚合物。CTP中使用的典型催化剂是具有双膦或N-杂环卡宾辅助配体的Pd或Ni络合物。最近，已使用二亚胺连接的Ni络合物。然而，在大多数情况下，在高单体转化率和/或低催化剂负载量下，非生命途径占主导地位。我们在此报告了另一种Ni二亚胺催化剂，该催化剂在低催化剂负载量和高单体转化率下以链增长方式聚合3-己基噻吩。此外，我们阐明了链增长机制以及一条链转移途径。总的来说，这些研究提供了对由Ni二亚胺催化剂介导的共轭聚合物合成机理的见解。