Cover Picture: Group4 Metal Complexes of Phenylene-Salalen Ligands in rac-Lactide Polymerization Giving High Molecular Weight Stereoblock Poly(lactic acid)

The synthesis of high molecular weight stereoblock poly(lactic acid) of high isotacticity, which would crystallize in the stereocomplex phase, by the isoselective polymerization of racemic lactide, remains elusive. The synthesis of Group4-metal complexes of phenylene-salalen ligands featuring a broad structural diversity and a uniform wrapping tendency, enabled the deciphering of structure-activity relationships that led to the identification of catalysts combining high activity and high isoselectivity. More information can be found in the Full Paper by M. Kol etal. on page 11540.