The Search for New-Generation Olefin Polymerization Catalysts: Life beyond Metallocenes

Abstract
Even late transition metal complexes function as active and selective catalysts for α‐olefin polymerization. The discovery of a highly active family of catalysts 1 based on iron, a metal that had no previous track record in this field, has highlighted the possibilities for further new catalyst discoveries. As a result, an intense search has developed for new‐generation catalysts, in both academic and industrial research laboratories. R1=H, Me; R2=Me, iPr; R3=H, Me, iPr; R4=H, Me; X=halide.