New ¹⁹F NMR methodology reveals structures of molecules in complex mixtures of fluorinated compounds

Abstract

Although the number of natural fluorinated compounds is very small, fluorinated pharmaceuticals and agrochemicals are numerous. 19F NMR spectroscopy has a great potential for the structure elucidation of fluorinated organic...

19F-centred NMR analysis of mono-fluorinated compounds

“…Application of the 19 F-centered approach to a very complex mixture of chloramination by-products is presented elsewhere. 30 …”

“…Application of this methodology to a very complex mixture of compounds produced by chloramination of a single fluorinated molecule is presented elsewhere. 30 …”

Tailoring the Recognition Property of a 19F-Labeled Gallium-Based NMR Probe: The Influence of the Metal Center

“…Another approach to achieve enantiodifferentiation is through NMR experiments in chiral-oriented media, which utilizes anisotropic NMR data to elucidate the stereochemical information of chiral molecules. ,− Recently, 19 F NMR-based enantiodifferentiation methods have gained popularity owing to the low background and the high sensitivity of 19 F chemical shifts to the change of the surrounding microenvironment. Various 19 F-labeled derivatization agents are developed, allowing the enantioanalysis of chiral amines and alcohols. − In addition to the chemical derivatization, the dynamic recognition between a 19 F-labeled molecular probe and enantiomers was also explored to produce diastereoisomeric probe-analyte adducts. − In this approach, the intermolecular chemical exchange has to be slower than the NMR time scale in order to produce characteristic 19 F NMR signals assignable to each enantiomer. − Bell and coworkers demonstrated an interesting 19 F-centered NMR approach, representing a step further toward structural determination without the need for separation . Previously, we are engaged in the development of 19 F-labeled probes bearing confined chiral binding pockets.…”

“…32−34 Bell and coworkers demonstrated an interesting 19 F-centered NMR approach, representing a step further toward structural determination without the need for separation. 35 Previously, we are engaged in the development of 19 probe-Al, M = Al), we were able to achieve a rapid enantiodifferentiation of a series of Lewis basic analytes, including alcohols, amides, cyclic ethers, sulfoxide, etc. 28,29 Despite the wide analyte scope, anhydrous solvents are usually needed for the detection because of the competitive binding of water toward the Al metal center.…”

Pure shift FESTA: An ultra‐high resolution NMR tool for the analysis of complex fluorine‐containing spin systems

“…However, with only one 19 F per molecule, simple one-dimensional (1D) 19 F NMR provides limited structural information. Multidimensional methods utilising fluorine-proton ( 19 F-1 H) [12][13][14][15][16][17][18] or fluorine-carbon ( 19 F-13 C) correlations, 19,20 or both, [21][22][23][24] can be used to circumvent overlap in 1 H NMR spectra by dispersing signals over multiple dimensions. In particular, the two-dimensional (2D) GET-SERF experiment provides crucial conformational information through n J HF couplings to a specific 19 F atom whilst removing the effects of all other J HH and J HF .…”