One-pot electrosynthesis of substituted imidazolinium and tetrahydropyrimidinium salts from secondary alkyldiamines: An electrochemical route toward ionic liquids

(Chemical Equation Presented) A one-pot electrosynthetic procedure has been developed to afford imidazolium and tetrahydro-pyrimidinium cationic derivatives from secondary alkyl diamines in neutral media. To this end, electrochemical oxidation of a series of aliphatic diamines (1-9) has been investigated. Mechanistic information is provided from analysis of the cyclic voltammetry data and identification of intermediate species and final products. The coexistence of two first-order chemical reactions, Cα-H and Cα-Cβ, at the radical cation level leading to identical final products is suggested to justify not only the nature but also the yields of the salts obtained. © 2009 American Chemical Society.