Ruthenium complexes of sterically-hindered pentaarylcyclopentadienyl ligands

The synthesis of ruthenium complexes incorporating an overcrowded pentaarylcyclopentadienyl ligand has been investigated, and higher efficiency has been reached using chlorine-functionalised precursors when compared with their brominated counterparts. A new methodology for the preparation of chlorocyclopentadienes has been developed which is well adapted for highly sterically hindered compounds and works with either electron rich or poor systems. Preparation of chlorine functionalised intermediates has been developed which is well adapted for highly sterically hindered compounds both with either electron rich or poor systems.