Homogeneous Catalysis Using Lanthanide Amidinates and Guanidinates

摘要: For decades, the organometallic chemistry of rare earth elements was largely dominated by cyclopentadienyl ligand and its ring-substituted derivatives. A hot topic in current organolanthanide is search for alternative sets which are able to satisfy coordination requirements large lanthanide cations. Among most successful approaches this field use amidinate ligands general type [RC(NR ′ )2]− (R = H, alkyl, aryl; R cycloalkyl, aryl, SiMe3) can be regarded as steric equivalents. Closely related guanidinate anions [R2NC(NR SiMe3; SiMe3). Two or coordinate a ion form metallocene-like environment allows isolation characterization stable though very reactive amide, hydride species. Mono- trisubstituted complexes also readily available. Various amidinates guanidinates have turned out efficient homogeneous catalysts, example, ring-opening polymerization reactions. This article covers success story their transition from mere laboratory curiosities catalysts.