The alkaline hydrolysis of a series of homologous reactants constituted by two reactive centers bridged by a methylene spacers chain, the 1,n-bis(2-azidepyridinium)alkanes (n = 3, 4, 5, 6, and 8), is investigated. The reaction under pseudo-first-order condition was followed by ultraviolet-visible spectrophotometry. The presence of clear isosbestic point suggests the absence of stable intermediates. However, the intermediates 1-(2-azidepyridinium), n-(2-pyridone)alkanes (monocationic compounds), were isolated and characterized as well the reaction end products 1,n-(2-pyridone)alkanes (noncharged compounds). The kinetic analysis fitted to a two-step consecutive reaction, where the k 1 /k 2 values demonstrate the larger reactivity of the first step over the second one, especially for shorter bridged reactants. The OH − reaction order is one for each step. Although Debye-Hückel law was obeyed, the experimental point at ionic strength zero is much higher than the extrapolated one. In addition, the k 1 values substantially decrease as KCl is added especially for shorter homologous whereas the effect on k 2 is almost negligible. Simple charge density effects as a function of the spacer's length do not explain the observations. On the other hand, from the pronounced anion selectivity inhibition effects on k 1 for the shorter derivatives, the existence of an equilibrium involving a conformer, a "sandwich-type" complex with the OH − between the two pyridinium rings, with an "open-stretched" conformer is proposed. For short-bridged reactants, the complex conformer