AbstractThe advancement of stereoregular polymerization techniques for linear 1,3‐dienes has enabled the production of polymers with precise stereocontrol, influencing their physical and chemical properties significantly. While 1,3‐butadiene and isoprene yield diverse stereoregular polymers, cyclic dienes have received less attention due to catalyst challenges and limited application in the rubber industry. However, the growing interest in bio‐based monomers, particularly those derived from terpenes and terpenoids, has revitalized interest in cyclic monomers with conjugated double bonds. This study investigates 1‐vinylcyclohexene (VCH) polymerization using [OSSO]‐type titanium complexes 1–2, revealing significant regio‐ and stereoselectivity. Catalyst 2, incorporating cumyl substituents, demonstrates superior performance, yielding highly isotactic poly(VCH) with 3,4‐insertion predominance. It is also shown that the polymerization of S‐4‐isopropenyl‐1‐vinyl‐1‐cyclohexene (IVC), a bio‐based monomer, results in a highly isotactic polymer. Finally, the copolymerization results of IVC with two linear terpenes to obtain copolymers derived entirely from renewable sources are also reported.
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