Ring-Opening Polymerization of rac-Lactide with Aluminum Chiral Anilido-Oxazolinate Complexes

نویسندگان

  • Shi Bian
  • Srinivas Abbina
  • Zhengliang Lu
  • Edward Kolodka
  • Guodong Du
چکیده

A series of dimethylaluminum complexes (L1a-i )AlMe2 (2a-i, where HL1a-i = 2-(2'-ArNH)phenyl-4-R1-oxazoline) bearing chiral, bidentate anilido-oxazolinate ligands have been prepared and characterized. Six of the complexes, in the presence of an alcohol cocatalyst, are shown to be active initiators for the stereoselective ring-opening polymerization of rac-lactide in toluene solution and under bulk conditions, yielding polylactides with a range of tacticity from slightly isotactic to moderately heterotactic. The reactivity and selectivity of these catalysts are discussed on the basis of the effect of their substituents.

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عنوان ژورنال:

دوره 33  شماره 

صفحات  -

تاریخ انتشار 2014