A structure–function study of the surface tension changes of m-xylene in the presence of fluorous 1H-1,2,3-triazoles and tetrazoles

A study of surface tension measurements in m-xylene has shown that new hybrid 1H-1,2,3-triazoles and tetrazoles bearing perfluoroalkylethyl and -methyl substituents in combination with n-alkyl (lipophilic), n-alkoxymethyl (mildly hydrophilic), or methoxy(triethylenoxy)methyl (hydrophilic) substituents do have considerable surfactant properties. The properties of those with lipophilic substituents, especially those with alkyl chains of 8 carbons (or possibly more) border on erratic, while those with mildly hydrophilic or hydrophilic substituents exhibit highly predictable behaviour that is consistent with current understanding of surfactants. The change from two methylene spacer groups (perfluoroalkylethyl) to one methylene spacer group (perfluoroalkylmethyl) [equal to increasing the fluorine content], and the change from triazole to tetrazole nucleus, impart very significant increases on surface activity, whereas increases in the chain length of n-alkyl or perfluoroalkyl substituents have incremental effects.

Assessment of the surface activity of 28 fluorous 1,2,3-triazoles and 6 fluorous tetrazoles, along with 2 non-fluorous triazoles, through surface tension measurements in m-xylene, has provided information on the major factors that contribute to ordered surface activity within these closely related classes of compounds.Figure optionsDownload as PowerPoint slideHighlights
► Surface activity measurement of 34 hybrid, fluorous triazoles and tetrazoles.
► Examines systematic variations in F, N and O content, and length and position of substituents.
► Conclusions about the most favourable factors for surface active behaviour.