Wei Chuanzhi, Guo Lulu, Zhu Cheng, Cui Chunming
State Key Laboratory of Elemento-Organic Chemistry and Frontiers Science Center of New Organic Matter, Nankai University, Tianjin, 300071, China.
Haihe Laboratory of Sustainable Chemical Transformations, Tianjin, 300192, China.
Angew Chem Int Ed Engl. 2025 Jan 10;64(2):e202414464. doi: 10.1002/anie.202414464. Epub 2024 Oct 22.
The preparation of polyolefins with high polar monomer contents (above 20 mol %) has long been a challenge. Half-titanocenes (Cp')[HCN(Ar)]BOTiCl bearing bulky electron-donating N-heterocyclic boryloxy ligands have been designed and synthesized. The complexes (Cp*)[HCN(Ar)]BOTiCl (2, Ar=2,6-iPrCH; 5, Ar=2,4,6-MeCH) supported by Cp* and the boryloxy ligands have been shown to efficiently catalyze the copolymerization of ethylene and long chain α-olefins. In particular, precatalyst 5 enabled the controlled synthesis of poly(ethylene-co-9-decen-1-ol) with unprecedented high polar monomer contents up to 32.1 mol % while maintaining the high catalytic activity. The structural analysis and DFT calculations disclosed that the bulky and strong electron-donating boryloxy ligands could effectively stabilize cationic active species. The mechanical studies on the hydroxyl-functionalized copolymers disclosed that they exhibited high strength and toughness because of the existence of hydrogen bonds in the polymer network.
制备高极性单体含量（高于20摩尔%）的聚烯烃长期以来一直是一项挑战。已设计并合成了带有庞大供电子N-杂环硼氧基配体的半茂钛（Cp'）[HCN（Ar）]BOTiCl。由Cp和硼氧基配体支撑的配合物（Cp）[HCN（Ar）]BOTiCl（2，Ar = 2,6-iPrCH；5，Ar = 2,4,6-MeCH）已被证明能有效催化乙烯与长链α-烯烃的共聚反应。特别地，预催化剂5能够可控地合成具有高达32.1摩尔%的前所未有的高极性单体含量的聚（乙烯-co-9-癸烯-1-醇），同时保持高催化活性。结构分析和密度泛函理论计算表明，庞大且强供电子的硼氧基配体能够有效稳定阳离子活性物种。对羟基官能化共聚物的力学研究表明，由于聚合物网络中存在氢键，它们表现出高强度和韧性。
