Effects of Amine Oxide Surfactants on Reactions of Bromide and Hydroxide Ions with Methylnaphthalene-2-Sulfonate

Temperature effects upon aqueous micellar-assisted decarboxylation of 6-nitrobenzisoxazole-3-carboxylate and its 5-methyl derivative

“…In the region where 6-NBIC is located specific interaction could come into play. We do not know the site of 6-NBIC at the interface, but we may think that 6-NBIC is located closer to butyl head groups rather than to other alkyl head groups, for the important "hydrophobic" interactions that come into play in big-head surfactants, already observed in the soft-hard ion discrimination [30,31]. This would imply a more significant modification of the hydration shell going from initial to transition state (related to increased entropy of activation) and a minor electrostatic interaction due to decreased distance between charges due to the bulkiness of alkyl moieties (related to an increase in the enthalpy of activation).…”

Hoechst 33258 as a pH‐Sensitive Probe to Study the Interaction of Amine Oxide Surfactants with DNA

“…It has already been shown that small variation in the surfactant structure can induce significant changes in the aggregation properties. [16,17] In particular, it was recently observed that modification of the hydrophobic The use of Hoechst 33258 (HO) as a fluorescent probe to characterize the interactions between DNA and pH-sensitive amphiphiles is discussed. In the case of amine oxide amphiphiles dodecyldimethylamine oxide (DDAO) and p-dodecyloxybenzyldimethylamine oxide (pDoAO), the decrease in fluorescence emission, which signals DNA-amphiphile association, is accompanied by a large hypsochromic shift in the emission maximum of the bound probe; this eventually reaches a value characteristic of HO in a neutral or slightly basic environment.…”

Vesicular Catalysis of an SN2 Reaction: Toward Understanding the Influence of Glycolipids on Reactions Proceeding at the Interface of Biological Membranes

“…Similar conclusions were made as a result of the observation that the reaction is also catalyzed in zwitterionic micelles. 17,19,58 However, the micellar bimolecular rate constant for bromide ions was lower by a factor of at most about 2. More importantly, the binding constant of bromide ions to zwitterionic micelles is about 250 times lower than that to cationic micelles.…”

“…The reaction was followed at 320 or 326 nm for 2-methyl-4-nitrobenzenesulfonate (MNBS) and the 2-alkylnaphthtalenesulfonates (AlkONS), respectively, on a Perkin-Elmer λ5 or λ12 spectrophotometer, thermostated with a Haake DC50 water bath at 35.0 ± 0.1 °C. Following the reaction of MNBS at 320 nm instead of the commonly used wavelength of 280 nm − allowed following the reaction up to higher amphiphile concentrations, since at higher wavelength light scattering (and changes in light scattering) becomes less important. Rate constants were measured with an accuracy of 10%.…”