(Phosphine-sulfonate)Pd(Me)(DMSO) catalyzed copolymerization of ethylene and 3,3,3-trifluoropropene (TFP) allows the synthesis of linear copolymers with high fluorine contents of up to 15 wt % (8.9 mol % TFP). C and F NMR analyses of the copolymers were performed, showing that most of the incorporated TFP is located in the polymer backbone. Copolymerization of ethylene- with TFP revealed that TFP is inserted into Pd-D bonds in 1,2- as well as in 2,1-mode, although 1,2-insertion is slightly preferred. Chain transfer after TFP insertion is exclusively observed following 2,1-insertion. With higher TFP incorporation, an increase in the ratio of internal to terminal double bonds was detected in the H NMR spectra. This indicates that, in the case of 2,1-insertion of TFP, chain walking is facilitated relative to direct chain release after β-H transfer to the palladium center.
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http://dx.doi.org/10.1021/mz5004344 | DOI Listing |
J Org Chem
January 2025
Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
The copolymerization of ethylene with polar monomers presents a significant challenge. While palladium catalysts have shown promise, nickel catalysts are more economical but suffer from poor activity. Previous studies suggest that the isomerization step involved in the nickel-catalyzed polymerization may influence the catalyst activities.
View Article and Find Full Text PDFBiomacromolecules
January 2025
Department of Chemistry, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States.
Injectable biomaterials play a vital role in modern medicine, offering tailored functionalities for diverse therapeutic and diagnostic applications. In ophthalmology, for instance, viscoelastic materials are crucial for procedures such as cataract surgery but often leave residues, increasing postoperative risks. This study introduces injectable fluorescent viscoelastics (FluoVs) synthesized via one-step controlled radical copolymerization of oligo(ethylene glycol) acrylate and fluorescein acrylate.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, California 90095, United States.
We applied a classifier method to predict palladium catalysts for the formation of nonalternating polyketones via the copolymerization of CO and ethylene; current examples are limited to using phosphine sulfonate and diphosphazane monoxide supporting ligands. With the reported workflow, we discovered two new classes of palladium complexes capable of achieving the synthesis of nonalternating polyketones with a lower CO content than those made by known palladium catalysts. Our results show that we doubled the number of classes of palladium compounds that can catalyze the formation of this type of polymer.
View Article and Find Full Text PDFLangmuir
January 2025
Department of Chemistry, Indian Institute of Technology Patna, Patna 801103, Bihar, India.
Polyoxometalates (POMs) are composed of nanometric metal-oxide anions and have rich solution chemistry. In this class, Keggin POMs have been identified as the most influential inorganic additives for aqueous nonionic soft matter systems. POMs being at the borderline of classical ions and charged colloids possess fascinating solution properties; the present work aims to delve deeper into the interactions between nanoions and nonionic soft matters from a spectroscopic point of view.
View Article and Find Full Text PDFACS Macro Lett
January 2025
Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China.
Efficient synthesis of cyclic polymers remains a frontier challenge. We report here that macromolecular transesterification during a pseudoblock copolymerization process can be utilized for such a purpose. Organobase-catalyzed ring-opening alternating copolymerization of 3,4-dihydrocoumarin and epoxide is conducted with four-armed poly(ethylene oxide) (PEO) as a macroinitiator.
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