Cis-Specific Chain Transfer Ring-Opening Metathesis Polymerization Using a Vanadium(V) Alkylidene Catalyst for Efficient Synthesis of End-Functionalized Polymers

Highly efficient synthesis of end-functionalized polymers has been achieved by combined cis -specific ring-opening metathesis polymerization (ROMP) of norbornene with terminal olefins (1-hexene, allyltrimethylsilane (ATMS), etc.) as the chain transfer (cross metathesis) agent at 80 °C in the presence of V(CHSiMe 3 )(N-2,6-Cl 2 C 6 H 3 )[OC(CF 3 ) 3 ](PMe 3 ) 2 . The ROMP proceeds with high activity and high cis selectivity (97–98%) upon addition of PMe 3, and the M n values could be controlled by varying the concentration of terminal olefins; the activity at 80 °C was not affected by the ATMS concentrations (5.0–50.0 mol %, TOF 1860–1890 min –1 ((1.12–1.13) × 10 5 h –1 )).