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Creators/Authors contains: "Welch, John T"

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  1. ; ; ; ; (, Physical Chemistry Chemical Physics)
    The influence of fluoroalcohols on peptide folding was studied. 
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    Free, publicly-accessible full text available January 22, 2026
  2. ; ; ; (, Molecules)
    Novel tetrafluoro-λ6-sulfanyl-containing oligomers prepared by visible light-promoted addition of 1,4-(bis-chlorotetrafluoro-λ6-sulfanyl) benzene or 1,3-(bis-chlorotetrafluoro-λ6-sulfanyl) benzene to either 1,4-diethynyl benzene or the 1,3-diethynyl isomers form hard, stress resistant thin films on spin casting. The isomeric oligomers were utilized to establish a structure-function relationship for the mechanical properties of films prepared from the oligomers. The Young’s moduli of 145-nm-thick cured films could reach 60 GPa. The measured hardnesses, between 1.57 and 2.77 GPa, were more than double those of polymethyl methacrylate (PMMA) films. Curing of the tetrafluoro-λ6-sulfanyl-containing polymer films by UV irradiation resulted in coatings that exhibited remarkable hardness and modulus with good surface adhesion to silicon. 
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  3. ; ; (, The Journal of Organic Chemistry)
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  4. ; ; (, Organic & Biomolecular Chemistry)
    null (Ed.)
    Site specific introduction of the polar hydrophobic trifluoromethyl-λ 6 -tetrafluorosulfanyl (CF 3 SF 4 ) group can effectively control the secondary structure of a heptapeptide, the minimum repeat unit of an α-helix. The structural influence of CF 3 SF 4 -containing amino acid on the heptapeptide was established using NMR methods. 
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  5. ; (, ChemBioChem)
    null (Ed.)
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  6. ; ; ; ; (, Organic & Biomolecular Chemistry)
    null (Ed.)
    The influence of pentafluorosulfanylation on biological activity has been revealed in numerous comparative studies of biologically active compounds, but considerably less is known about the influence of pentafluorosulfanylation on reactivity. Among the distinctive properties of the pentafluorosulfanyl group is the profound dipole moment that results from introduction of this substituent. It has been shown that dipolar effects coupled with the steric demand of the SF 5 group may be employed to influence the stereochemistry of reactions, especially those processes with significant charge separation in the transition state. The Staudinger ketene-imine cycloaddition reaction is an ideal platform for investigation of dipolar control of diastereoselectivity by the pentafluorosulfanyl group. 
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  7. ; ; ; ; (, Journal of Polymer Science)
  8. ; ; ; ; ; (, European Journal of Organic Chemistry)