Aluminum methyl, alkoxide and α-alkoxy ester complexes supported by 6,6′-dimethylbiphenyl-bridged salen ligands: synthesis, characterization and catalysis for rac-lactide polymerization

A series of mono- and dinuclear salen aluminum complexes could efficiently catalyze the ROP of rac-LA, producing isotactic enriched and atactic PLA, respectively. In solution, the association/dissociation equilibrium of the carbonyl group was found in the model O-lactate complexes.