Organotransition-Metal Metallacarboranes. 18. n6,n5-Benzyltetramethylcyclopentadienide(1-) as a Bridging Ligand in Multilevel Iron-Cobalt Sandwich Complexes

摘要

Bimetallic and polymetallic linked sandwich complexes are attracting increasingattention, in part because they provide a bridge between molecular chemistry and materials science and also because they have potential for utilization in novel electronic devices. In our research, a current focus of interest is the design and construction of multiunit metal sandwich complexes that incorporates cyclic planar C2B3 or pyramidal C2B4 carborane units together with C6 (arene) or C5 (cyclopentadienyl)aromatic hydrocarbon ligands. The carborane ligands serve a multifold purpose: to provide electronic stabilization for unusual or otherwise unstable structures (e.g., multidecker complexes); to promote electron delocalization between metal centers; and to serve as points of attachment for external functional groups and for intermolecular linkage of sandwich units. One of our objectives is the controlled, stepwise assembly of electron-delocalization oligomers and polymers containing multidecker sandwich units whose metal atoms are capable of communicating with each other electronically.