来源：ACS Publications
Kinetic resolution polymerization (KRP) of nonpolar conjugated dienes remains a significant challenge because of their flexible coordination modes and subtle reactivity differences between isomers. Herein, we report that by fine-tuning ligand steric environments and metal centers, the KRP of naturally occurring (E,Z)-β-ocimene (E/Z-Oc) was successfully realized by using catalysts 1 and 5 to afford a stereoregular E-homopolymer while simultaneously isolating a Z-isomer with high purity (>95.5%). Moreover, complex 1 enabled to polymerize Z-Oc in highly isotactic trans-1,4 selectivity in moderate activity and rapidly polymerized E-Oc in an atactic 1,2-regularity-enriched mode, which may provide the block copolymer of poly(E-Oc)-b-poly(Z-Oc) by stepwise loading of Z-Oc followed by E-Oc. Using complex 2, the block copolymer of poly(E-Oc)-b-poly(Z-Oc) was obtained in one pot. Real-time 1H nuclear magnetic resonance kinetic studies revealed that E-Oc polymerized significantly faster than Z-Oc, depending on the ligand structure. Density functional theory calculations further indicated that the isomer-dependent regio- and stereoselectivity originated from chain-end and geometric site control mechanisms. This work demonstrated that rare-earth metal catalysts provide a powerful platform for KRP of complex terpene-derived dienes, offering a sustainable strategy for both isomer separation and precise polymer synthesis.