The stepped reaction of decafluorobiphenyl with thiophenol studied by in situ 19F NMR spectroscopy

Organocatalyzed synthesis of fluorinated poly(aryl thioethers)

“…For further comparison of different catalyst systems and catalyst loadings, we selected 15 min as a benchmark reaction time. The large dispersity observed (entry 1, Table 1 ) may be the result of cross-linking or branching via multiple substitutions on the arene ring and would be consistent with the high reactivity of hexafluorobenzene 3 , 23 – 26 . However, examination of the 19 F NMR spectrum reveals a clean singlet indicative of a symmetrically substituted perfluoroarene ring and therefore the dispersity of the isolated material is more likely a result of kinetic quenching from the precipitation of the polymeric material.…”

“…Poly(aryl thioethers) are traditionally prepared via nucleophilic aromatic substitution (S N Ar) under conditions that utilize stoichiometric amounts of base, extended reaction times, or in some cases, high temperatures 16 – 21 . Although these conditions have been utilized for the incorporation of perfluoroaryl-containing monomers into poly(aryl thioethers) 22 , they are not ideal, given the propensity of perfluoroarenes to undergo multiple substitutions 3 , 23 – 26 potentially leading to uncontrolled branching or cross-linking. Additionally, the stoichiometric amount of salt generated under standard S N Ar conditions could hamper further applications such as casting films to prepare hydrophobic surfaces.…”

Proton conducting ABA triblock copolymers with sulfonated poly(phenylene sulfide sulfone) midblock obtained via copper-free thiol-click chemistry

“…50 To avoid metal-catalyzed click-reactions, the blocks were connected using a thiolfluoro click-chemistry. Decafluorobiphenyl (DFBP) was employed as it readily reacts with thiolate anions under mild conditions 51,52 and has been reported to improve nanophase separation when used as a linker for sulfonated block copolymers. 53,54 By varying the molecular weight of the constituting blocks, ABA triblock-copolymers with different compositions and different IEC can be obtained, allowing us to explore the nanostructure-property relationship of this new class of charged block copolymers.…”

Quantitative analysis of sitagliptin using the19F-NMR method: a universal technique for fluorinated compound detection

“…3 To achieve qualitative and quantitative determination of pharmaceuticals in one step, 1 H quantitative NMR (qHNMR) needs no specic standard references and consumes a small amount of organic solvent when compared with other instrumental methods. This technique has recently been one of the most routinely used approaches for the quantitative analysis of new compounds due to its intrinsic advantages, including higher sensitivity and natural abundance when compared to the other nuclei (e.g., 31 P and 13 C). 4,5 However, qHNMR also has its problems and limitations.…”

“…Furthermore, without the interference from the water peak and less interference from endogenous or exogenous backgrounds, 19 F-NMR is more suitable for the quantitative analysis of compounds in a biological background and commercial formulations than 1 H-NMR. 7 Based on these attributes, the 19 F-NMR method has been applied to identication of structures, [8][9][10][11] monitoring of the reaction process, 12,13 and quantitative analysis of uorine-substituted drug molecules. 7,[14][15][16][17][18] However, the studies on the research methodology of 19 F-NMR for the quantitative analysis of uorinated pharmaceuticals have not been reported as well as its comparison with the 1 H-NMR method.…”