1361946-41-9Relevant academic research and scientific papers
Preparation and characterization of aluminum alkoxides coordinated on salen-type ligands: Highly stereoselective ring-opening polymerization of rac -lactide
Chen, Hsiao-Li,Dutta, Saikat,Huang, Pei-Ying,Lin, Chu-Chieh
, p. 2016 - 2025 (2012)
A series of salen-type ligands (L1H2-L 6H2) with sterically bulky cumyl groups have been synthesized. Reaction of these ligands with AlMe3 yields the mononuclear aluminum complexes [LAlMe] (1-3) or dinuclear species [L 2Al2Me4] (4-6), respectively. Further reaction of [LAlMe] (1-3) with benzyl alcohol produces [LAl(OBn)] (1a-3a), respectively. Solid-state structural studies reveal that complexes 1a and 2a are mononuclear; however, complex 6 is a dinuclear species. Aluminum alkoxides 1a-3a are highly stereoselective in the ROP of rac-lactide, producing polylactide (PLA) with 94-97% enantiomeric selectivity (Pm) at high conversion. Their high enantioselectivity leads to PLA with high Tm (205 °C). The polymerization of l-lactide by these complexes also shows good living features with narrow PDI values (Mw/Mn = 1.06-1.25) signaling less or no transesterification, which can be further verified by MALDI-TOF mass spectrometric analysis.
