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(CHSiMe3)­(N-2,6-Cl2C6H3)­[OC­(CF3)3]­(PMe3)2. The ROMP proceeds with high activity and high cis selectivity (97–98%) upon addition of PMe3, 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) × 105 h–1)).