at Google ScholarTitle data
Ghosh, Swarup ; Glöckler, Eduard ; Wölper, Christoph ; Tjaberings, Alexander ; Gröschel, André H. ; Schulz, Stephan:
Heteroleptic β-Ketoiminate Magnesium Catalysts for the Ring-Opening Polymerization of Lactide.
In: Organometallics.
Vol. 39
(2020)
Issue 23
.
- pp. 4221-4231.
ISSN 1520-6041
DOI: https://doi.org/10.1021/acs.organomet.0c00168
Abstract in another language
A series of heteroleptic β-ketoimine magnesium complexes L1L′1 Mg2Cp*(1), L22Mg2Cp2 (2), L12Mg2(OAr)2 (3 and 4), and L22Mg2(OAr)2 (5 and 6) (L1 = Me2NC2H4NC(Me)CHC(Me)O, L′1 = Me2NC2H4NC(CH2)CHC(Me)O, L2 = Me2NC3H6NC(Me)CHC(Me)O; Ar = Ph and 2,6-t-Bu2-C6H3) with different steric and electronic properties were synthesized. 1 and 3–6 adopt binuclear structures in the solid state and in solution, whereas 2 forms a monomer/dimer equilibrium in solution. Complexes 1 and 2 showed very poor activity in the ring-opening polymerization (ROP) of racemic-lactide (rac-LA), whereas heteroleptic phenoxide complexes 3–6 are active polymerization catalysts at variable temperature in solution in the absence of any co-initiator, yielding isotactic-enriched polylactide (PLA). The catalytic activity and stereoselectivity is controlled by the electronic and steric properties of the phenoxide substituent and reaction temperature. Kinetic studies with catalyst 3 and 5 proved the first-order dependence on monomer concentration, and mechanistic studies showed that the polymerization reactions follow the coordination insertion mechanism (CIM).
Further data
| Item Type: | Article in a journal |
|---|---|
| Refereed: | Yes |
| Institutions of the University: | Research Institutions > Central research institutes > Bayerisches Zentrum für Batterietechnik - BayBatt Research Institutions Research Institutions > Central research institutes Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Polymer Materials for Electrochemical Storage > Chair Polymer Materials for Electrochemical Storage - Univ.-Prof. Dr. André Gröschel |
| Result of work at the UBT: | No |
| DDC Subjects: | 500 Science > 540 Chemistry |
| Date Deposited: | 24 Jul 2023 13:09 |
| Last Modified: | 02 Aug 2023 07:53 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/86305 |