Synthesis of ZnII and AlIII Complexes of Diaminocyclohexane‐Derived Ligands and Their Exploitation for the Ring Opening Polymerisation of rac‐Lactide

Two series of ligands based on diaminocyclohexane (DACH) have been prepared and successfully complexed to AlIII and ZnII metal centres. Solution and solid‐state studies reveal a tendency to form mono‐ or bis‐ligated forms depending on the steric bulk of the ligand. These complexes have been tested for their ability to ring open rac‐lactide. AlIII based complexes generally gave atactic PLA after a polymerisation time of 1–2 days. The ZnII complexes, were found to be more active and furnished PLA with a slight heterotactic bias. Several ligands and complexes based on diaminocyclohexane are reported. Full structural characterisation has been carried out as well as assessment of these complexes for their ability to polymerise rac‐lactide.