Journal ArticleDOI
Cubane‐Type Polynuclear Zinc Complexes Containing Tridentate Schiff Base Ligands: Synthesis, Characterization, and Ring‐Opening Polymerization Studies of rac‐Lactide and ε‐Caprolactone
TLDR
In this article, a polynuclear zinc complexes containing tridentate Schiff base ligands were successfully synthesized and fully characterized using single crystal X-ray diffraction, which showed good catalytic activity towards the ring-opening polymerization (ROP) of rac-lactide (rac-LA) and ǫcaprolactone (ǫ-CL) under solvent free conditions.Abstract:
New polynuclear zinc complexes containing tridentate Schiff base ligands were successfully synthesized and fully characterized. The solid-state structure of the complexes was determined using single crystal X-ray diffraction. The complexes display a tetranuclear cubane-like core structure [Zn4O4] and sowed good catalytic activity towards the ring-opening polymerization (ROP) of rac-lactide (rac-LA) and ɛ-caprolactone (ɛ-CL) under solvent-free conditions. The polylactic acid (PLA) obtained from rac-LA showed isotactic enrichment, as proved by homonuclear decoupled 1H NMR analysis. These complexes also showed good activity and superior control towards the ROP of rac-LA and ɛ-CL in the presence of benzyl alcohol as a co-initiator. Furthermore, Kinetic studies demonstrated that the ROP of rac-LA and ɛ-CL has a first order dependence on both monomer (rac-LA and ɛ-CL) and catalyst concentration.
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Citations
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Highly active zinc catalyst for the controlled polymerization of lactide.
Laurie E. Breyfogle,Charlotte K. Williams,SK Choi,Wonwoo Nam,VG Young,Marc A. Hillmyer,William B. Tolman +6 more
TL;DR: In this paper, the authors reported the preparation, structural characterization, and detailed lactide polymerization behavior of a new Zn(II) alkoxide complex, (L(1)ZnOEt)(2) (L (1) = 2,4-di-tert-butyl-6-{[(2'-dimethylaminoethyl)methylamin]methyl}phenolate).
Journal ArticleDOI
Heterolepic β-Ketoiminate Zinc Phenoxide Complexes as Efficient Catalysts for the Ring Opening Polymerization of Lactide.
Swarup Ghosh,Pascal Schäfer,Dennis Dittrich,Christoph Scheiper,Phillip Steiniger,Gerhard Fink,Agnieszka N. Ksiazkiewicz,Agnieszka N. Ksiazkiewicz,Alexander Tjaberings,Christoph Wölper,André H. Gröschel,Andrij Pich,Andrij Pich,Andrij Pich,Sonja Herres-Pawlis,Stephan Schulz +15 more
TL;DR: Polymers with high average molecular weight (M n) and moderately controlled molecular weight distribution (MWDs) are synthesized and characterized and 1 and 5 showed a living polymerization character and kinetic studies on the ROP of L–LA proved first order dependencies on the monomer concentration.
Journal ArticleDOI
Tetranuclear Zn complex covalently immobilized on sulfopropylsilylated mesoporous silica: An efficient catalyst for ring opening reaction of epoxide with amine
Divya Jadav,Pooja Shukla,Rajib Bandyopadhyay,Yoshihiro Kubota,Sourav Das,Mahuya Bandyopadhyay +5 more
TL;DR: In this paper, the tetranuclear Zn complex was used for the ring opening reaction of propylene oxide with morpholine producing the corresponding β-aminoalcohols, which achieved a maximum 95% conversion rate.
Journal ArticleDOI
Syntheses, structures and catalytic activity of tetranuclear Mg complexes in the ROP of cyclic esters under industrially relevant conditions
TL;DR: The very high turnover frequencies (TOF) of 9600 h-1 (rac-LA) and 24’1 (ε-CL) prove that 1 belongs to the most active biocompatible, sustainable and nontoxic ROP catalysts under industrially relevant conditions.
Journal ArticleDOI
Dinuclear Zn(II) and tetranuclear Co(II) complexes of a tetradentate N2O2 Schiff base ligand: Synthesis, crystal structure, characterization, DFT studies, cytotoxicity evaluation, and catalytic activity toward benzyl alcohol oxidation
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