0635509 - ÚOCHB 2026 RIV US eng J - Journal Article
Théron, B. - Vlk, L. - Chlupatý, T. - Penouilh, M. J. - Procházková, Eliška - Malacea-Kabbara, R. - Le Gendre, P. - Růžička, A.
Flexible Biguanide Mono- and Bimetallic Zinc Complexes for the Ring-Opening (Co)polymerization of Lactides.
ACS Catalysis. Roč. 15, č. 11 (2025), s. 9117-9129. ISSN 2155-5435. E-ISSN 2155-5435
Institutional support: RVO:61388963
Keywords : biguanide * zinc * ROP * copolymer * immortal polymerization
Impact factor: 11.7, year: 2023 ; AIS: 2.948, rok: 2023
Method of publishing: Open access
Result website:
https://doi.org/10.1021/acscatal.5c01335DOI: https://doi.org/10.1021/acscatal.5c01335

One of the most urgent social demands on polymer chemistry is the design of an inexpensive, efficient, robust, and nontoxic catalyst for the preparation of biodegradable polymers with good control of its properties. The nonsymmetric ditopic doubly deprotonable biguanide proligand (substituted 4,6-dimethoxypyrimidin-2-yl-guanidine 1) with dynamic behavior forms monometallic as well as bimetallic complexes when reacted with one or two equivalents of Et2Zn or Zn[N(SiMe3)2]2. In monometallic complexes 2 and 4, zinc atoms primarily occupy a position within the six-membered ring. In the bimetallic complexes 3 and 5, the adjacent ethylzinc and zinc amide moieties are coordinated in a bidentate fashion by the guanidinate-like part of the ligand. The ethylzinc complexes 2 and 3 are inactive in the ring-opening polymerization (ROP) of rac-lactide, whereas the performance of the zinc amides 4 and 5 activated by i PrOH is among the highest observed. In complex 5, the positions of the two zinc ions can be interchanged, which could explain the ability of this nonsymmetrical bimetallic complex to promote the ROP of lactide (LA) at both Zn sites to form polylactide (PLA) chains with a unimodal molecular-weight distribution. One-pot preparation of various di- or oligoblock copolymers is possible by the sequential living copolymerization of beta-butyrolactone and L-, D- or rac-lactides, leading to the precise control of its microstructure.
Permanent Link: https://hdl.handle.net/11104/0366579