Synthesis and Hydrolysis of Chemodegradable Cationic Surfactants Containing the 1,3-Dioxolane Moiety

Article abstract of DOI:10.1007/BF02541476

In acid-catalyzed reactions of long-chain aliphatic aldehydes (Ia-d where a = n-C7H15; b = n-C9H19; c = n-C11H23; d = n-C13H27), and tridecan-7-on (Ie) with 3-chloro-1,2-propane-diol, 2-alkyl- and 2,2-dihexyl-4-chloromethyl-1,3-dioxolanes (IIa-e) were obtained.They were reacted with anhydrous dimethylamine to obtain, respectively, 2-alkyl- and <(2,2-dihexyl-1,3-dioxolan-4-yl)methyl>dimethylamines (IIIa-e), which were quaternized with methyl bromide to obtain the desired ammonium bromides (IVa-e).The structure and purity of the compounds was proved by mass spectrometry and proton magnetic resonance spectroscopy.Additionally, <(2-methyl-1,3-dioxolan-4-yl)methyl>trimethylammonium bromide and <(2,2-dimethyl-1,3-dioxolan-4-yl)methyl>trimethylammonium bromide were synthesized as nonaggregating standards.Hydrolysis reactions of the synthesized ammonium bromides were performed by 0.1 M hydrochloric acid in 1:1 (vol/vol) 1,4-dioxane-water mixtures at 50, 60 and 70 deg C.Rate constants of hydrolysis reactions were determined by observing carbonyl group formation at 280 nm.The hydrolytic reactivity of the studied surfactants (IVa-c,e) was determined under unaggregated conditions.Compound IVd showed decreased reactivity.The length of the 2-alkyl group has a minor effect on rate constant values.The influence of various substituents at the C-4 atom of the 2-nonyl-1,3-dioxolan-4-yl derivatives on rate constants was also investigated. KKEY WORDS: <(2-Alkyl-1,3-dioxolan-4-yl)methyl>trimethylammonium bromides, <(2,2-dihexyl-1,3-dioxolan-4-yl)methyl>trimethylammonium bromide, chemodegradable acetal-type cationic surfactants, kinetic and thermodynamic parameters of 1,3-dioxolane ring hydrolysis.