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The fluoronitrenoid metal complexes FNCoF2 and FNRhF2 as well as the first ternary RhVI and IrVI complexes NIrF3 and NRhF3 are described. They were obtained by the reaction of excited Group‐9 metal atoms with NF3 and their IR spectra, isolated in solid rare gases (neon and argon), were recorded. Aided by the observed 14/15N isotope shifts and quantum‐chemical predictions, all four stretching fundamentals of the novel complexes were safely assigned. The F−N stretching frequencies of the fluoronitrenoid complexes FNCoF2 (1056.8 cm−1) and FNRhF2 (872.6 cm−1) are very different and their N−M bonds vary greatly. In FNCoF2, the FN ligand is singly bonded to Co and bears considerable iminyl/nitrene radical character, while the N−Rh bond in FNRhF2 is a strong double bond with comparatively strong σ‐ and π‐bonds. The anticipated rearrangement of FNCoF2 to the nitrido CoVI complex is predicted to be endothermic and was not observed. [ABSTRACT FROM AUTHOR]

The fluoronitrenoid metal complexes FNCoF2 and FNRhF2 as well as the first ternary RhVI and IrVI complexes NIrF3 and NRhF3 are described. They were obtained by the reaction of excited Group‐9 metal atoms with NF3 and their IR spectra, isolated in solid rare gases (neon and argon), were recorded. Aided by the observed 14/15N isotope shifts and quantum‐chemical predictions, all four stretching fundamentals of the novel complexes were safely assigned. The F−N stretching frequencies of the fluoronitrenoid complexes FNCoF2 (1056.8 cm−1) and FNRhF2 (872.6 cm−1) are very different and their N−M bonds vary greatly. In FNCoF2, the FN ligand is singly bonded to Co and bears considerable iminyl/nitrene radical character, while the N−Rh bond in FNRhF2 is a strong double bond with comparatively strong σ‐ and π‐bonds. The anticipated rearrangement of FNCoF2 to the nitrido CoVI complex is predicted to be endothermic and was not observed. [ABSTRACT FROM AUTHOR]

The fluoronitrenoid metal complexes FNCoF2 and FNRhF2 as well as the first ternary RhVI and IrVI complexes NIrF3 and NRhF3 are described. They were obtained by the reaction of excited Group‐9 metal atoms with NF3 and their IR spectra, isolated in solid rare gases (neon and argon), were recorded. Aided by the observed 14/15N isotope shifts and quantum‐chemical predictions, all four stretching fundamentals of the novel complexes were safely assigned. The F−N stretching frequencies of the fluoronitrenoid complexes FNCoF2 (1056.8 cm−1) and FNRhF2 (872.6 cm−1) are very different and their N−M bonds vary greatly. In FNCoF2, the FN ligand is singly bonded to Co and bears considerable iminyl/nitrene radical character, while the N−Rh bond in FNRhF2 is a strong double bond with comparatively strong σ‐ and π‐bonds. The anticipated rearrangement of FNCoF2 to the nitrido CoVI complex is predicted to be endothermic and was not observed. [ABSTRACT FROM AUTHOR]

The fluoronitrenoid metal complexes FNCoF2 and FNRhF2 as well as the first ternary RhVI and IrVI complexes NIrF3 and NRhF3 are described. They were obtained by the reaction of excited Group‐9 metal atoms with NF3 and their IR spectra, isolated in solid rare gases (neon and argon), were recorded. Aided by the observed 14/15N isotope shifts and quantum‐chemical predictions, all four stretching fundamentals of the novel complexes were safely assigned. The F−N stretching frequencies of the fluoronitrenoid complexes FNCoF2 (1056.8 cm−1) and FNRhF2 (872.6 cm−1) are very different and their N−M bonds vary greatly. In FNCoF2, the FN ligand is singly bonded to Co and bears considerable iminyl/nitrene radical character, while the N−Rh bond in FNRhF2 is a strong double bond with comparatively strong σ‐ and π‐bonds. The anticipated rearrangement of FNCoF2 to the nitrido CoVI complex is predicted to be endothermic and was not observed. [ABSTRACT FROM AUTHOR]

A de novo designed class of peptide-based fluoropolymers composed of fluorinated aliphatic amino acids as main components is reported. Structural characterization provided insights into fluorine-induced alterations on β-strand to α-helix transition upon an increase in SDS content and revealed the unique formation of PPII structures for trifluorinated fluoropeptides. A combination of circular dichroism, fluorescence-based leaking assays and surface enhanced infrared absorption spectroscopy served to examine the insertion and folding processes into unilamellar vesicles. While partitioning into lipid bilayers, the degree of fluorination conducts a decrease in α-helical content. Furthermore, this study comprises a report on the proteolytic stability of peptides exclusively built up by fluorinated amino acids and proved all sequences to be enzymatically degradable despite the degree of fluorination. Herein presented fluoropeptides as well as the distinctive properties of these artificial and polyfluorinated foldamers with enzyme-degradable features will play a crucial role in the future development of fluorinated peptide-based biomaterials., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Substituting the P 1 position in bovine pancreatic trypsin inhibitor (BPTI) is known to heavily influence its inhibitory activity towards serine proteases. Side-chain fluorinated aliphatic amino acids have been shown to alter numerous properties of peptides and proteins and thus are of interest in the context of BPTI. In our study, we systematically investigated the site-specific incorporation of non-canonical amino acids into BPTI by microwave-assisted solid-phase peptide synthesis (SPPS). Inhibitor activity of the variants was tested towards the serine protease α-chymotrypsin. We observed enhanced inhibition of two fluorinated BPTIs compared to wild type and hydrocarbon variants. To further investigate the complexes, we performed X-ray structure analysis. Our findings underline the power fluorine offers as a tool in protein engineering to beneficially alter the effects on phenomena as protein-protein interactions., Competing Interests: The authors declare no competing financial interests., (This journal is © The Royal Society of Chemistry.)

The fluoronitrenoid metal complexes FNCoF 2 and FNRhF 2 as well as the first ternary Rh VI and Ir VI complexes NIrF 3 and NRhF 3 are described. They were obtained by the reaction of excited Group-9 metal atoms with NF 3 and their IR spectra, isolated in solid rare gases (neon and argon), were recorded. Aided by the observed 14/15 N isotope shifts and quantum-chemical predictions, all four stretching fundamentals of the novel complexes were safely assigned. The F-N stretching frequencies of the fluoronitrenoid complexes FNCoF 2 (1056.8 cm -1 ) and FNRhF 2 (872.6 cm -1 ) are very different and their N-M bonds vary greatly. In FNCoF 2 , the FN ligand is singly bonded to Co and bears considerable iminyl/nitrene radical character, while the N-Rh bond in FNRhF 2 is a strong double bond with comparatively strong σ- and π-bonds. The anticipated rearrangement of FNCoF 2 to the nitrido Co VI complex is predicted to be endothermic and was not observed., (© 2020 The Authors. Published by Wiley-VCH GmbH.)