Functionalized double-chain surfactant 1 (potassium O,O ‘-didodecylphosphorodithioate) was synthesized. Its small unilamellar vesicles were characterized by dynamic laser light scattering and differential scanning calorimetry and its giant vesicles by phase-contrast optical microscopy. Also, 1's giant vesicles containing fluorescent dye 4a (5-carboxyfluorescein) or 4b [5-(dodecanamido)fluorescein] were characterized by epifluorescence microscopy. In a pH 9.0 borate buffer at 25 °C, vesicular 1 reacted with 2 (2-chloroethyl phenyl sulfide), a simulant for the chemical warfare agent mustard [bis(2-chloroethyl) sulfide], to give 5 [S-[(2-phenylthio)ethyl] O,O‘-didodecylphosphorodithioate], involving capture of reactive intermediate cation 9 (1-phenylthiocyclopropane) by the anion of 1. This reaction was accompanied by the precipitation of 5, which resulted in wounding/destruction of the vesicles and the release of dye 4a (from giant vesicles). The combination of the conversion of 2 into 5 and dye release suggests the potential of vesicular systems for simultaneous decontamination and signaling of chemical agents. 2 hydrolyzed to give only 6 [2-(phenylthio)ethanol] in the pH 9.0 buffer at 25 °C.

All of the stereoisomeric forms of the surfactant, sodium 3-[2-methyl-4,5-bis(hexadecyloxymethyl)-1,3-dioxolan-2-yl]propane-1-sulfonate, have been prepared:  the enantiomers (+)-1 and (−)-1, the racemate (±)-1 (by two different methods), and meso 2 and meso 3. Vortexed vesicles of these materials were characterized by dynamic laser light scattering, to give vesicle sizes, and by differential scanning calorimetry, to give bilayer phase transition temperatures and associated enthalpies. Different calorimetry results were obtained for (+)-1 [(−)-1], (±)-1, 2, and 3. In particular, a comparison of the results for (+)-1 [(−)-1] and (±)-1 indicated the operation of enantiomer discrimination. The criteria of the “absolute” method of stereochemistry applied to this study were not completely fulfilled.

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