Synthesis of Al(III) silsesquioxane complexes and their exploitation for the ring opening polymerisation of rac-lactide

In this paper we report the synthesis and characterisation of silsesquioxane tethered Al(III) complexes. The complexes have been characterised by multi-nuclear NMR spectroscopy and depending upon the bulk of the ligand either Al(L)Me2 or Al(L)2Me complexes were isolated. We also report the first solid-state structure of a tethered Al–silsesquioxane complex of the form Al(L)Me2. All complexes and heterogeneous analogues were tested for the ring opening polymerisation of rac-lactide, with narrow molecular weight polylactide formed.