Zinc and Magnesium Complexes Bearing Oxazoline-Derived Ligands and Their Application for Ring Opening Polymerization of Cyclic Esters.

ABSTRACT: A family of different substituents aza(oxazoline) ligand-based zinc and magnesium complexes were synthesized. These complexes can catalyze ring opening polymerization of ?-caprolactone (?-CL) and lactide (LA) to produce poly-?-caprolactone and polylactide with good conversions. Polymerization studies showed that the zinc complexes 1a-4a had moderate activity toward LA and ?-CL polymerization. In situ IR spectroscopy research of zinc complexes showed that the N-donor group-substituted complexes had higher activity than that of the O-ether donor group. The substituted analogies and the flexibility of the amino backbone had a distinct influence on the activity of LA and ?-CL polymerization. The alternates of zinc with magnesium produced complexes 5a-8a, which achieved an obviously increased polymerization activity. Among these magnesium complexes, 7a showed the highest activity in the polymerization of LA. At [M]/[cat] = 1000, the reaction progress was stabilized in 5 min with up to 97% conversion of a monomer at ambient temperature.

SUBMITTER: Duan R 

PROVIDER: S-EPMC6645436 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature