Zinc complexes coordinated by bipyridine-phenolate ligands as an efficient initiator for ring-opening polymerization of cyclic esters
A series of zinc complexes coordinated by different bipyridine-phenolate (BpyPh) ligands, 2-([2,2′-bipyridin]-6-yl)-4,6-di-tert-butylphenol (BpyPh2,4-tBu-H, 3) and 2-([2,2′-bipyridin]-6-yl)-4-(tert-butyl)phenol (BpyPh4-tBu-H, 4) have been synthesized. The reaction of BpyPh2,4-tBu-H with ZnEt2 gave a...
Saved in:
Published in | Polymer (Guilford) Vol. 56; pp. 237 - 244 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Elsevier Ltd
15.01.2015
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | A series of zinc complexes coordinated by different bipyridine-phenolate (BpyPh) ligands, 2-([2,2′-bipyridin]-6-yl)-4,6-di-tert-butylphenol (BpyPh2,4-tBu-H, 3) and 2-([2,2′-bipyridin]-6-yl)-4-(tert-butyl)phenol (BpyPh4-tBu-H, 4) have been synthesized. The reaction of BpyPh2,4-tBu-H with ZnEt2 gave a six-coordinated complex of [(BpyPh2,4-tBu)2Zn] (5) with the distorted octahedral geometry. However, the dinuclear complexes of [(BpyPh)Zn(μ-OBn)]2 (6 and 7) were formed when benzyl alcohol was added and then can be converted to mononuclear zinc benzylalkoxide species by the increased temperature. The ε-CL and L-LA polymerizations initiated by complex 6 showed the living characteristics of narrow molecular weight distribution (PDIs < 1.15) and the capability of block copolymer synthesis demonstrated by the formation of PCL-b-PVL and PCL-b-PHB. The ring-opening polymerizations of cyclic esters initiated by complex 5, however, was not effective possibly due to the highly steric hindered metal center.
[Display omitted]
•Designed ligands were obtained via a simple, one-pot synthetic process.•Well controlled ring-opening polymerization of various cyclic esters was achieved.•Different block copolymers of lactones have been synthesized. |
---|---|
Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0032-3861 1873-2291 |
DOI: | 10.1016/j.polymer.2014.12.001 |