Efficient and mild reaction conditions were developed for the catalytic carbonylation of fluorinated epoxides to their corresponding β-lactones. Six new lactones with fluorinated side chains were prepared in high isolated yields. These lactones were polymerized to form a series of new poly(β-hydroxyalkanoate)s with fluorinated side chains, and their properties were examined with respect to their hydrocarbon analogs. Finally, copolymerizations were performed with fluorinated lactones and β-butyrolactone, which resulted in tapered copolymers rather than the expected random copolymers.
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http://dx.doi.org/10.1016/j.tet.2008.03.108 | DOI Listing |
J Phys Chem A
January 2025
Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany.
The persistent organic radical 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO) protects its NO radical center by four methyl groups. Two of them are arranged tightly (t) on one side of the six-membered puckered heterocycle, and the other two more openly (o) on the other side. It is shown by OH stretching infrared spectroscopy in heated supersonic jet expansions that the hydrogen bond and aromatic ring of a first solvating benzyl alcohol have almost no preference for either side.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
College of Safety Science and Engineering, Nanjing Tech University, Nanjing 211816, China.
An experimental investigation is conducted to identify the optimal blend of fluoroethylene carbonate (FEC), 3,3,3-trifluoropropylene carbonate (TFEC), and various fluorinated ethers, including 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether (HFE), 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE), and bis(2,2,2-trifluoroethyl) ether (BTE), to enhance the performances of lithium-ion cells at high voltage. The cell incorporating TTE exhibits a significantly superior capacity for retention after long-term cycling at 4.5 V, which might be attributed to the improved kinetics of lithium ions and the generation of a thin, reliable, and inorganic-rich electrode-electrolyte interface.
View Article and Find Full Text PDFMetabolites
January 2025
Institute of Toxicology, Core Unit Proteomics, Hannover Medical School, 30623 Hannover, Germany.
Charge-free gaseous molecules labeled with deuterium H (D) atoms elute earlier than their protium-analogs H (H) from most stationary GC phases. This effect is known as the chromatographic H/D isotope effect (IE) and can be calculated by dividing the retention times () of the protiated ( ) to those of the deuterated () analytes: IE = /. Analytes labeled with C, N or O have almost identical retention times and lack a chromatographic isotope effect.
View Article and Find Full Text PDFJ Agric Food Chem
January 2025
CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences; Future Technology College, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
Many diseases and pests are fond of the backs of leaves, making wraparound deposition essential for enhancing agrochemical utilization and minimizing environmental hazards. We present a superhydrophobic surface decorated with fluorinated-SiO nanoparticles on the adaxial (front) side, improving sprayed droplet wraparound behaviors and achieving a 10-fold increase in abaxial (backside) deposition without using an electrostatic sprayer. Solid-liquid contact electrification boosts the positive charge-to-mass ratio of rebound spraying from 17 to 454 nC g, with the abaxial surface acquiring opposite electric charges at kilovolt-level voltages.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing 314001, China.
The ground-state charge generation (GSCG) in photoactive layers determines whether the photogenerated carriers occupy the deep trap energy levels, which, in turn, affects the device performance of organic solar cells (OSCs). In this work, charge-quadrupole electrostatic interactions are modulated to achieve GSCG through a molecular strategy of introducing different numbers of F atom substitutions on the BTA3 side chain. The results show that 8F substitution (BTA3-8F) and 16F substitution (BTA3-16F) lead to different patterns of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy level changes.
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