Introducing Dynamic Features into Rigid Post-metallocene Ligand Frameworks
DescriptionMetallocenes have found effective and versatile applications as tunable catalysts for polymerization and organic transformations, yet the search for enhanced activity, electrophilicity and scope in reactivity continues. Developments for post-metallocenes and non-cyclopentadienyl olefin polymerization catalysts have led to superior efficiencies and selectivity, and novel materials with unprecedented properties. First, this project concerns the introduction of dynamic structural features into rigid ligand scaffolds and their impact upon (a) the stability and reactivity of corresponding complexes and catalysts, and (b) the properties of resultant polymers. Fundamental investigations of hindered rotation and structural consequences of helical modules in novel organometallic analogues of phenanthrene will be undertaken. Second, the development of ligand frameworks bearing an alkene moiety is proposed, because the greater flexibility of the chelating sigma-alkenyl (compared with aryl) complexes can influence potentially diverse insertion reactions with unsaturated substrates. Furthermore, the impact of alkenyl substituents upon catalysis may be more potent due to their proximity to the metal center. The underlying applied aim is to modify catalytic behavior (and polymer characteristics) by manipulating the rotating and/or flexible components introduced into the rigid ancillary ligand.
|Effective start/end date||1/01/10 → 26/03/13|