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Updated: Jan 9, 2026

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Published on: February 7, 2017
Chiral poly(aza-norbornene) derivatives with tunable tacticity and living ROMP capability
Jing Bai1,2, Yu Wang1, Yisong Wang3
1Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences Beijing 100190 China weiyou@iccas.ac.cn ywang507@iccas.ac.cn.
None:
Ring-opening metathesis polymerization (ROMP) is a powerful tool to produce various polymers with diverse structures and functions, but its tacticity controllability, especially for enantio-pure monomers, is relatively unexplored. The challenge lies in both the difficulty of achieving chiral monomers and the control of head/tail regioselectivity during ROMP. We herein report the synthesis and application of a sulfonamide derivative of commercial chiral Vince lactam. The easily available monomer showed simultaneous living ROMP capability and tunable head/tail regioselectivity with commercial Ru-based catalysts. More specifically, the use of the Grubbs' III catalyst (Ru-3) gave rise to head-to-tail regioselectivity, leading to isotactic "living" polymers. In contrast, the use of cyclometalated Ru-based catalysts (Ru-4 and Ru-5) enabled the formation of head-to-head polymers, leading to syndiotactic polymers. Detailed experimental and DFT studies suggest that the regioselectivity is dominated by the chain-end-control mechanism. The precise microstructural tunability enables us to systematically investigate thermal properties, crystallinity, and dielectric properties of the hydrogenated ROMP polymers.
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