We have developed a method that involves the generation of a “cation pool” using low-temperature electrolysis, and then its reaction with nucleophiles under non-oxidative conditions. This one-pot method solves problems associated with conventional oxidative generation of cations and their in situ reaction with nucleophiles, and provides an efficient method for direct oxidative carbon−carbon bond formation. As an example of this method, generation of cation pools from carbamates by low-temperature electrolysis (−72 °C) and their reactions with carbon nucleophiles such as allylsilanes, enol silyl ethers, and enol acetates were examined and the desired products were obtained in good yields. Aromatic compounds and 1,3-dicarbonyl compounds can also be utilized as carbon nucleophiles. The present method was also applied to combinatorial parallel synthesis using a robotic synthesizer.

Marked effects of protonation (ionization) of tetradecyldimethylamine oxide on the viscoelastic properties of the micelle solutions were found. The effect strongly suggests the short-range attractive interaction between the headgroups of the nonionic (deprotonated) and the cationic (protonated) species. The zero shear viscosity reached a maximum at the half-ionized state (the degree of ionization R ) 0.5) and the value was larger than that of the nonionic species (R ) 0) or the cationic species (R ) 1) by more than 2 orders of magnitude. At a surfactant concentration C of 0.1 mol/kg, approximately single Maxwell behavior was observed as R approached 0.5 from either side. For the half-ionized micelles (R ) 0.5) in 0.1 mol/kg NaCl solutions, the steady-state compliance J e 0 decreased with C with an exponent of 2.1 ( 0.2, suggesting the presence of an entangled network of flexible threadlike micelles. The relaxation time, on the other hand, exhibited a nonlinear dependence on C. It was about 0.1 s and remained nearly constant in the range C > 0.1 mol/kg (regime I), whereas it increased with C in the range of C < 0.09 mol/kg (regime II) with an exponent slightly larger than 1. The single Maxwell behavior was observed in regime I. The regime shift was not controlled by the ratio C/m s , m s representing the NaCl concentration. Effects of NaCl concentration and the temperature on the viscoelastic properties were also examined at R ) 0.5. Cryo-transmission electron micrographs clearly showed a highly entangled network in the solution for R ) 0.5, while much smaller micelles for R ) 0. Contrary to the expectation from the rheological results, a highly entangled network was also observed in the solution for R ) 1.

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