Abstract
Four lanthanum alkoxides stabilized by a carbon-bridged bis(phenolate) ligand were synthesized and their catalytic behavior for the ring-opening polymerization of L-lactide was explored. Reactions of [(MBMP)LaCp(THF)2] (MBMP2− = 2,2′-methylene-bis(6-tert-butyl-4-methyl phenoxo)) with HOCH2Ph, HOCH2CF3, HOCH(CH3)2, and HOCH2CH2N(CH3)2, respectively, in a 1:1 molar ratio in THF gave the dimeric lanthanum alkoxo complexes [(MBMP)Ln(Sm-OR)(THF)2]2 (OR = OCH2Ph (1), OCH2CF3 (2), OCH(CH3)2 (3), OCH2CH2N(CH3)2 (4)]. These complexes were well characterized, and the definitive molecular structure of complex 1 was determined. It was found that complexes 1 to 4 are efficient initiators for the ring-opening polymerization of L-lactide. The structure of the alkoxo groups has a significant effect on the catalytic behavior, and complex 2 can initiate L-lactide polymerization in a controlled manner.
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Li, B., Qi, R., Yao, Y. et al. Synthesis and characterization of carbon-bridged bis(phenolate) lanthanum alkoxides and their catalytic behavior for the polymerization of L-lactide. Chin. Sci. Bull. 57, 4442–4447 (2012). https://doi.org/10.1007/s11434-012-5330-9
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DOI: https://doi.org/10.1007/s11434-012-5330-9