[reaction: see text]. N-propargylamino acids and peptides including them can be efficiently derivatized in aqueous media with a wide variety of (hetero)aryl halides by cross-coupling reactions catalyzed by palladium on carbon (10% Pd/C).

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Spiropyridines, a novel series of C 2 -symmetric ligands, can be obtained in moderate yields by means of Co(I)-catalyzed double cocyclization between bis-alkynenitriles and alkynes. This one-step method allowed the first synthesis of the interesting 7,7′-and 8,8′-spyropyridines from acyclic precursors.

Conductivity (σ) measurements are performed on micellar systems consisting of tetradecyltrymethylammonium bromide (TTAB) in the presence of n-butanol (BuOH). It is found that σ vs BuOH molarity dependence at fixed TTAB concentration shows an unusual sinusoidal behavior. Other parameters of the systems are studied and an approximation to the conductivity of the system is made. The unusual dependence of conductivity on alcohol concentration at fixed surfactant concentration is discussed and some evidence of the competition of the viscosity of water−alcohol solution and the degree of ionization on conductivity of the systems are presented, rather than a phase transition as it was proposed earlier.

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