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Licensed Unlicensed Requires Authentication Published by De Gruyter January 22, 2016

New heteroscorpionate lanthanide complexes for ring-opening polymerisation of ɛ-caprolactone and rac-lactide

  • Alberto Scrivanti EMAIL logo , Marco Bortoluzzi and Mattia Gatto
From the journal Chemical Papers

Yttrium and lanthanum amido-complexes with bis(pyrazol-1-yl)acetates in their coordination spheres were studied as the catalysts in ɛ-caprolactone and lactide ring-opening polymerisation. A high molecular mass poly(ɛ-caprolactone) (PCL) was obtained in almost quantitative yield under mild conditions. rac-Lactide polymerisations were less efficient and required quite harsh experimental conditions to obtain atactic PLA samples with moderate yields. The average chain-length of PCL was dependent upon the choice of the metal centre and the presence of substituents on the pyrazole rings of the ancillary ligand. The ground-state geometries of the complexes and the first stages of ɛ-caprolactone polymerisation were computationally modelled by means of DFT calculations.

Presented at the XXV. International Conference on Coordination and Bioinorganic Chemistry, Smolenice, Slovakia, 31 May–5 June 2015.


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Received: 2015-3-11
Revised: 2015-4-15
Accepted: 2015-4-20
Published Online: 2016-1-22
Published in Print: 2016-1-1

© 2015 Institute of Chemistry, Slovak Academy of Sciences

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